Posts filed under 'Database'
There are times when the coexistence of 64 and 32 bit code on the same machine can cause all sorts of seemingly strange issues.
One of them just occurred to me while trying to run the ASPx demos from Developer Express, my main provider of .Net components (the best supplier I’ve ever been able to find).
I was getting the following error:
The ‘Microsoft.Jet.OLEDB.4.0’ provider is not registered on the local machine:
It may look otherwise, but this error is generally due to either of two thing:
- you don’t have Office 2007/2010 Jet drivers installed
- or you are running a 32 bit application in a default x64 environment.
The first issue is easy to solve, just download the Access 2010 Database Engine from Microsoft (works with Access 2007 databases as well).
For the second one, the fix is also easy enough:
- For Windows 2008: Navigate to Server Manager > Roles > Web Server (IIS) > Internet Information Services (IIS) Manager, then look under your machine name > Application Pool.
- For Windows 7: Navigate to Programs > Administrative Tools > Internet Information Services (IIS) Manager, then look under your machine name > Application Pool.
Under there you can call the DefaultAppPool’s advanced settings to change Enable 32-Bits Applications to True:
You may have to restart the service for it to take effect but it should work.
References
Updates
- 10DEC2011: Updated driver link to use the Access 2010 engine.
- 03APR2010: Added instructions for Windows 7
- 12FEB2009: Added reference to Scott’s article.
- 28OCT2008: Original version
October 28th, 2008
My trusty old gigantic Sony Vaio is about 4 years old. It served me well and still works but it’s about to become my main development machine for the next couple of months and I can’t afford to have it die on me during that time.
It was time to get something as gigantic and more up-to-date in terms of technology.
I use VMware on my main desktop to keep multiple OS setups that match typical configurations of my customer’s machines.
This allows me to test my software before deployment and make sure everything works as expected.
It saved me many times from strange bugs and I would consider these final tests to be a mandatory step before deployment.
My old trusty vaio would be hard pressed to run any of these without slowing down to a crawl.
I looked at some possible replacements. Initially I checked Lenovo’s offerings but they don’t seem to offer anything in large screen size (WUXGA 1920×1200) (Note, actually, they have, but not really for me).
Dito for Dell, not counting their humongous XPS M1730 luggable gaming machine that was wayyy over the top as a work computer, not to mention probably heavier than its volume in pure gold.
On a hint from a friend I checked out Apple’s online store and saw they had a nice Macbook Pro configuration. I went to check it out in the retail store close to my office and they had that exact specification in stock, so, in what must have been the highest rated expense/time-to-think ratio of any decision I ever took, well, I bought it…
The spec, some bragging rights:
- Macbook Pro 17″
- Core Duo T9500 2.6GHz processor
- nVidia 8600M GT 512MB graphics card
- 200GB 7200rpm drive
- Kingston 4GB DDR2 667MHz RAM
- Hi Resolution 17″ 1920×1200 glossy screen
It’s a very nice machine, Apple knows how to make nice hardware, there is no question there.
OSX has some cool features, some of them still a bit foreign to me and some minor annoyances are creeping up, like Thunderbird’s not picking up my system date and time settings and displaying the date in the wrong format (a pet peeve of me), probably not Apple’s fault but annoying nonetheless.
So far so good and while I don’t mind using OSX for my browsing, email and creative stuff, that machine is meant to be running Windows Server 2008 x64 as a development platform.
Why Windows Server 2008 x64?
Well, it has some excellent features, a smaller footprint than Vista, all the aero eye candy, is apparently noticeably faster than Vista and has none of the nagging security prompt (you are considered administrator though, so keeping safe is entirely up to you).
The 64 bit version can also address the full 4GB of RAM without limitation and all server features are optionally installable.
By default, the installation is actually pretty minimal and you have to set services and options to get Windows configured as a proper workstation. It is after all, meant to be a server.
Oh, I almost forgot that there is also support for HyperV, although you must make sure you download the right version (if you list all available downloads in your MSDN subscription, you’ll see some that are explicitly without that technology).
Installing Windows Server 2008 x64 is remarkably easy.
- Get your hands on the ISO from your MSDN subscription or an install DVD from somewhere else (like a MS event, or even as a free 240 days download from Microsoft).
- You’ll need to repackage the ISO as it won’t work properly (something to do with non-standard file naming options).
It’s fairly easy if you follow the instructions from Jowie’s website (cached version): you can get the ImgBurn software for free as well, which is a good find in itself. It should’t take more than 30 minutes to repackage the DVD.
- In OSX, go to Applications > Utilities > Boot camp and follow the instructions on screen.
You will be able to resize the default partition by just moving the slider. I left 60GB for OSX and allocated the rest to Windows. The good thing is that OSX can read Windows partitions, so you can always store data there. Windows however, can’t read the HFS+ mac file system, although there are some third-party tools that can do it [1] [2] [3].
- Insert your repackaged DVD and Bootcamp will have rebooted the machine.
After a few minutes of blank screen (and no HDD activity light to let you know something is happening), windows setup launches.
- You will be then prompted with the choice of partition to install to.
Select the one named BOOTCAMP, then click the advanced options button and click format.
From there one, windows will install everything, then reboot, then carry on installing, then reboot one last time.
- Now, insert your OSX recovery CD 1. It should automatically launch the driver installation.
Once done, you’ll reboot to a nice, full-resolution windows prompt.
- All drivers will have been installed correctly except the one for Bluetooth. To easily solve that issue, just go to Spencer Harbar’s website and read how to install the Bluetooth drivers. Takes 5 minutes tops.
The final touches
A few notes to quickly get things running as expected.
- Get the most of your configuration by following the list of tweaks from Vijayshinva Karnure from Microsoft India.
- There are more tweaks, and even more tweaks available as well (don’t forget to enable Superfetch).
- Microsoft has a whole KB entry on enabling user experience.
- In the Control Panel > System > Advanced System Settings > Advanced > Settings > Advanced > Processor scheduling, set to Programs instead of Background services.
- Activate your copy of Windows using Control Panel > System.
I was getting an error code 0x8007232B DNS name does not exist error. To force activation, just click on the Change Product Key button and re-enter the same key you used during install.
Windows will activate straight away.
- When booting your Macbook, press the Option key and you will be presented a list of boot choices.
- You can check on Apple’s Bootcamp webpage other information about how to use the track pad, keyboard layouts etc,
References
August 31st, 2008
Access programming is inherently single-threaded. That’s usually OK as most operations are sequential anyway and it keeps things simple at the programming level.
There are times though where the lack of ability to run code on another thread is sorely missing: anything that takes a long time to run will just freeze the application, making it unresponsive and appearing to be locked and about to crash to the user.
Checking for the existence of network paths
Checking for the existence of network paths (directories or files) is one of these issues that can freeze an application for 30 seconds or more if the folder is not accessible.
This is a type of problem that benefits greatly from running in a separate thread: it can take such a long time that the best way to check for these remote paths is to launch the verification for their existence outside of Access and somehow get the result back and cache it for the current session so we don’t have to suffer these delays again every time we check for that path’s existence.
One easy way to do achieve that goal is to create plain DOS batch files that execute hidden from view, create a result file when they complete their task and delete themselves automatically when they are finished.
How to use it
Download the sample database below then just add the FileUtilities, HashTable and MD5 modules to your project and you can use the code as such:
Dim status As AsyncDirectoryStatus
status = FileUtilities.PathExistAsync("\\123.45.67.89\shared folder")
The status variable will return either of the following values:
AsyncDirectoryStatus.OK if the path was found.AsyncDirectoryStatus.NotFound if the path was not found (either because it doesn’t exist or you don’t have the rights to access it).AsyncDirectoryStatus.Checking if the verification is in progress and we haven’t received a definite answer yet.
It’s up to you to decide how you want to handle that case. You could periodically check it, like I did in the example database, or you could disable the controls until you’re getting a confirmed result (by checking every time the user performs some action, like moving from record to record in a datasheet for instance).
You can call PathExistAsync as often as you want to check the status: it will not slow down your application (read the optional arguments section below though).
The result of the verification is cached, so querying the existence of the path is actually only done once; the result of subsequent queries for the same path is just instantly retrieved from memory.
Optional arguments
If you want to force the actual re-checking of a path without using the cached value, you can simply pass the ForceCheck optional parameter:
Dim status As AsyncDirectoryStatus
status = FileUtilities.PathExistAsync("\\123.45.67.89\shared folder", ForceCheck:=true)
The first time you query for a path (or force it to be rechecked) there will be a short 150ms delay to give a chance to the function to return its result straight away (in case the path can be resolved quickly).
This may not be desirable if you’re checking a bunch of directories at a time. For instance, this is what I do when my application launches:
' Check a bunch of paths in parallel
PathExistAsync strPathToQualityDocuments, NoDelay:=true
PathExistAsync strPathToFinancialDocuments, NoDelay:=true
PathExistAsync strPathToShippingDocuments, NoDelay:=true
PathExistAsync strPathToPurchasingDocuments, NoDelay:=true
By querying the existence of all these paths as soon as my application launches, I am starting the verification process without introducing delays in the application itself: each verification will start in its own process, in parallel to the main application.
Later in the application, when I need to actually use these paths, their result is likely to be known.
How it works
The FileUtilities module contains the main code.
In it, the PathExistAsync function works in slightly different ways depending on whether it’s the first time it is being called for a particular path or not.
The first time
The first time the function is called for a given path, we create in the user’s temporary folder the small batch file whose name is simply a MD5 hash (see below) of the path with .bat appended to it.
This batch file simply checks for the existence of the path and will create a small file (whose name is the MD5 hash of the path) with either 0 or 1 in it depending on the result of the verification.
We initially cache the status of the verification for the Path into the AsyncDirectories hashtable (see below) as Checking.
Example of batch file automatically created to verify a path:
IF NOT EXIST "\\123.56.78.9\going nowhere" GOTO NOTEXIST
echo 1 > "C:\DOCUME~1\Renaud\LOCALS~1\Temp\463C7367D8329BD6209A65A70A7DA08C"
GOTO END
:NOTEXIST
echo 0 > "C:\DOCUME~1\Renaud\LOCALS~1\Temp\463C7367D8329BD6209A65A70A7DA08C"
:END
DEL %0
The Batch file name is 463C7367D8329BD6209A65A70A7DA08C.bat where the long number is actually the MD5 hash of the path we’re checking \\123.56.78.9\going nowhere.
Getting back the result
Whenever the PathExistAsync function is called, we check the currently cached result from the AsyncDirectories hastable.
If it is still Checking then we try to verify if we the result file has been created from the running batch. If not, we just return the same status, if yes, we read the result from the file, save it in the hashtable and delete the result file.
Useful libraries
The code makes use of 2 extremely useful libraries that I end up using quite often:
a HashTable implementation.
It makes it easy to create hashtable objects (otherwise known as Associative Arrays) to store and retrieve key/value pairs quickly.
Hashtables are often used to cache data and can be thought of arrays where the index is a string value instead of an number.
Here I use a hashtable to keep track of the paths we’ve checked and their result.
a MD5 hash implementation.
MD5 is a way to get a somewhat unique fixed-length value from a chunk of data.
It’s a mathematical function that guarantees that a small change in input (say a single bit in the input data) has a large effect on the output value (a totally different number will be generated) and that you can’t reverse the function (you can’t obtain the input just by looking at the output).
It is often used in applications to transform sensitive data like passwords into unique values that can be (somewhat) safely stored because you can’t easily reverse a md5.
Well, MD5 are not secure any longer but here we just use their ability to transform our path into a unique number that we can easily use as a filename and a key for our hash to retrieve the current status of the path being checked.
Sample database
Download the PathExistAsync01.zip (67KB) containing the Access 2007 ACCDB database.
Download the PathExistAsync02b.zip (121KB) containing the MDB database1 (untested as I only have Access 2007).
License
Please refer to the source code in the database for the exact licensing terms.
Note that the license only refers to code by me. When code from other sources is used, you will have to conform to their own licensing terms.
This work is licensed under a Creative Commons Attribution 3.0 Unported License.
References
June 20th, 2008
This project provides a custom and enhanced message box replacement for the default MsgBoxfound in Access. A Test database containing all the code for Access 2007/2010/2013 is available at the bottom of this post.
(UPDATED Saturday 21OCT2014 to VERSION 1.10.)
What’s wrong with the default MsgBox
The default message box in Access is sometimes useful to warn, inform or ask confirmation from the user.
It has, however, a few drawbacks:
- It is bland: the standard message box does not even follow the currently selected Office colour scheme.
- The amount of text it can display is limited: if you try to display too much text it will be truncated.
- You can’t copy or save the content of the message.
- Because popup boxes are viewed as intrusive, people tend not to read them and end-up closing message boxes before they realize they may have contained useful information.
- They only displays plain text: you cannot format the message to draw attention to the key points.
- They are blocking, meaning that nothing can happen in the main application while the box is displayed (it can’t even shut down).
- It will only appear on the monitor that has the main Access application window, even though the message box may have been opened from a form on another monitor.
Sometimes you need to display an important message or require users to make take a decision.
Message boxes are not to be abused but they serve a useful purpose.
An enhanced message box
Rather than using the bland standard message box you can now have something a bit more customized.
Plain Text version of the enhanced custom message box under the Office Blue Colour Scheme:
RichText version of the enhanced custom message box under the Office Black Colour Scheme:
Here are the features of the enhanced message box:
- It is entirely compatible with the standard one: just change
MsgBox to Box
using find and replace should be enough (see tip below to avoid getting strange errors).
- It allows the user to simply click on a button to copy the content of the message to
the clipboard or save it to a text file to a configurable default location.
- It looks and feels like it belongs to the main application, following its colour scheme.
- It attempts to prevent users from blindly closing the modal box reading the message: buttons will first be inactive for a configurable amount of time. It’s not a perfect solution, but it is quite effective.
- There is a
RichBox version that can display rich HTML content, not just plain text, so important parts of the message can be formatted in a useful way.
- It is able to display large amount of data. While it’s not something you usually want, it may be useful for the message box to display more text in some situations (log or tracing information, legal documentation, etc).
- Rather than sprinkling your code with “
& vbCrLf & _” uglies, you can embed newlines in the text itself by using C-style “\n” escape sequences that will automatically be transformed into the appropriate newlines. Makes for clearer code and less typing.
- Because you get the source, you can easily customise the message box with new icons and colours to better match your overall application’s personality.
- It is non-blocking: if your application forces users to log-off after a certain amount of inactivity, the enhanced message box will just close rather than prevent Access from shutting down like the standard
MsgBox does. Of course, it’s up to you to decide how to handle that gracefully, if at all.
- It properly displays the expected button captions based on the language of the operating system, so it behaves very much like the default
MsgBox (for instance, it will properly display “Cancel” on English systems and “Annuler” on French ones).
- It also properly plays the system sounds associated with the type of message. You can also enable or disable the sound effect as needed.
- From of version 1.4, it will display on the correct monitor in a multi-monitor environment.
- Version 1.7 adds support for Unicode escape sequences within strings to display Unicode characters in the dialog box. This was added following the publication of this article about .Net Strings in VBA.
- Version 1.10 adds a feature that allows users to dismiss a particular message so it doesn’t appear again.
How to use it
Download the demo database below and copy (drag & drop) the following into your application:
- the
FormDialog form,
- the
Dialog module.
If you rename the FormDialog, make sure you replace any occurrence to it in the code, in particular in the Dialog module.
Since the enhanced message box is just a replacement for the standard one, you just use it like you would use the MsgBox.
'-----------------------------------------------------------------------------
' Simple use of the Plaintext box
' Note the use of n that will be converted into a newline
Dialog.Box "This is a plaintext message.\nClick OK to dismiss",
vbOKOnly + vbinformation, _
"Message Title"
'-----------------------------------------------------------------------------
' Getting the result back
Dim dr As vbMsgBoxresult
dr = Dialog.Box("Are you sure you want to delete?", _
vbYesNoCancel + vbQuestion, "Confirm action")
If (dr = vbYes) Then DeleteRecords
'-----------------------------------------------------------------------------
' Using named parameters
Dialog.Box Prompt:="All your bases are belong to us", _
Buttons:=(vbOkOnly + vbCritical), _
Title:="Bad error"
'-----------------------------------------------------------------------------
' Using the RichBox to display simple HTML
' The first line will be bold, then the word 'button' will be printed in red
' Here the \n will be escaped to '<br/>' tags to simulate newlines.
Dialog.RichBox "<strong>This is a bold message</strong>.\n" & _
"Click the <font color=""#FF0000"">button</font> to dismiss.",
vbOKOnly + vbInformation, _
"RichText Message Title"
Options
There are a few additional settings that can be used to change the behaviour of the enhanced message boxes.
Custom buttons
You can customise the button labels instead of using the default ones (thanks to Kristjan for the suggestion):
'-----------------------------------------------------------------------------
' Use custom labels. Buttons that are not labelled will not be displayed
' The returned value is either vbBt1, vbBt2 or vbBt3
Dim dr As vbMsgBoxresultEx
dr = Dialog.Box (Prompt:="This is a custom button label test.",
Buttons:=vbCustom + vbInformation, _
Title:="A custom message", _
LabelButton1:="Hit Button 1!", _
LabelButton2:="No!, Me! Me!", _
LabelButton3:="Forget it!")
If (dr = vbBt1) Then Debug.Print "Button 1 pressed!"
ElseIf (dr = vbBt2) Then Debug.Print "Button 2 pressed!"
ElseIf (dr = vbBt3) Then Debug.Print "Button 3 pressed!"
Button delay
One is that you can adjust the delay before the buttons become activated.
'-----------------------------------------------------------------------------
' Use the ButtonDelay to specify the time in seconds before the buttons become activated
' The default is 2s. Use 0 to activate the buttons immediately.
Dialog.Box Prompt:="All your bases are belong to us", _
Buttons:=(vbOkOnly + vbCritical), _
Title:="Bad error", _
ButtonDelay:=1
'-----------------------------------------------------------------------------
' Change the default delay value.
' To disable the activation delay
Dialog.DefaultButtonDelay = 0
' To make the user wait 3 seconds before they can press any button
Dialog.DefaultButtonDelay = 3
Beep
Another one is that you can enable or disable whether beeps should be played or not.
'-----------------------------------------------------------------------------
' Use AllowBeep to specify whether beeps should be played when the message box opens
' By default, they are.
Dialog.Box Prompt:="All your bases are belong to us", _
Buttons:=(vbOkOnly + vbCritical), _
Title:="Bad error", _
AllowBeep:=False
'-----------------------------------------------------------------------------
' Change the default behaviour. This is True by default.
Dialog.DefaultAllowBeep = False
Hide Buttons
You can also hide the Copy to clipboard and save to File buttons which are normally visible by default.
'-----------------------------------------------------------------------------
' Use AllowCopyToClipboard and AllowSaveToFile to specify whether to display
' the copy to clipboard and save to file buttons.
' By default, they are visible, but here we hide them.
Dialog.Box Prompt:="All your bases are belong to us", _
Buttons:=(vbOkOnly + vbCritical), _
Title:="Bad error", _
AllowCopyToClipboard:=False, _
AllowSaveToFile:=False
'-----------------------------------------------------------------------------
' Change the default behaviour. This is True by default.
Dialog.DefaultCopyToClipboardAllowed = False
Dialog.DefaultSaveToFileAllowed = False
Save Folder
It is recommended to set the the folder where we should save the content of the message when the user clicks the Save button on the message box.
'-----------------------------------------------------------------------------
' Change the save folder.
' By default, the text messages will be saved in the same directory as the database.
' Here we want them to be saved to a temp directory
Dialog.DefaultSavedTextFileFolder = "C\:temp"
These few settings make the enhanced message box more customizable.
Raw text and paths
By default, the enhanced dialog box will escape certain sequences in the message to convert them to their printable version:
- Escape sequences like
\n and \t are converted to newlines and tabs spaces
- Unicode sequences are converted to their symbol:
\u20ac is converted to the euro symbol €.
If you do not want this behaviour (for instance you need to display data that contains lots of \ characters), use the NoStrEsc option:
'-----------------------------------------------------------------------------
' By default, all messages are unescaped.
' Here however, we want to disable that so we can display
Dialog.Box Prompt:="A path c:\my\doc\file.doc", _
NoStrEsc:=True
'-----------------------------------------------------------------------------
' Change the default behaviour. This is False by default.
Dialog.DefaultNoStrEsc = True
Alternatively, you can use the helper function dialog.EscBackslash():
'-----------------------------------------------------------------------------
' Use EscBackslash() when you only want some portion of text
' to display '\' correctly, like paths.
' Here however, we want to disable that so we can display
Dialog.Box Prompt:="A path " & EscBackslash("c:\my\doc\file.doc")
Don’t display this message again
Based on suggestions (and on a feature I wanted to implement for a while), I added a way to allow the user to choose not to display a particular message again.
Note that this feature will only work for dialog boxes displaying a single vbOKOnly button. It makes some sense since if you ask the user to choose between multiple actions, you can’t really expect their choice to be the same every time the message is displayed.
To make the dialog box dismissable, you only need to provide it with a unique ID for the message, using the DismissID option:
'-----------------------------------------------------------------------------
' Use DismissID to allow the user to never show the message again.
Dialog.Box Prompt:="An annoying warning message", _
Buttons:= vbOKOnly + vbExclamation
DismissID:="1234ABC"
The user can then tick the box and this particular message will never be shown again (unless we reset the setting for it).
To ensure that the user’s choice is remembered even if the Access application is updated, the message’s DismissID is stored in the registry under:
HKCU\Software\VB and VBA Program Settings\<AppFileName>\DialogBox, where <AppFileName> is simply the name of your Access file (without the path).
You can easily re-enable a particular message or all messages from your code:
'-----------------------------------------------------------------------------
' Re-enable the display of a previously dismissed message:
Dialog.ResetDismissID "1234ABC"
'-----------------------------------------------------------------------------
' Re-enable the display of all messages:
Dialog.ResetAllDismissID
Large text
The standard MsgBox cannot display much text. On the other hand, there is no real limitation to the amount of text the Box and RichBox can display.
When the amount of information is too much to fit the maximum allowed size for the message box the text will overflow and can be scrolled up/down as necessary.
Limitations of the RichBox
The RichBox version relies on the normal TextBox control’s ability under Access 2007 to display RichText wich is nothing more than lightweight HTML.
Because font size may be varying a lot in the message, it becomes very difficult to accurately predict the size of the box needed to display the whole message.
Short of implementing a complete HTML engine, we have to rely on some assumptions to display HTML.
The risk is that sometimes the content may not properly fit the TextBox control in some circumstances.
If you use the RichBox, thoroughly try displaying your messages and tweak the HTML as necessary to include additional lines or non-breaking spaces to ensure that the result looks good.
If you don’t overuse font size and don’t display in multiple fonts the RichBox should do the right thing most of the time.
Don’t overuse the RichBox to display colourful messages. There is a fine line between being informative and tasteless. Keep colours and formatting where it is useful.
I think that in most cases, the plain text version Box is more than enough.
How it works
The code makes extensive use of Win32 API calls.
Most of the hard work is done in the FomDialog class form. There is too much there to really go into the details but you are welcome to have a look at the commented code.
The code relies also on a utility function from Stephen Lebans used to calculate the size of of text. I have made some minor modification to that code so I would refer you to his original implementation if you are interested in calculating TextBox sizes for forms or reports.
In the code for the FormDialog, I re-implement some of the expected functionalities of the MsgBox: proper arrangement of the buttons, displaying of the appropriate icon, etc.
Once this is done, we calculate the size of the textbox needed to display the whole of the message.
In the case of RichText, we first use Application.PlainText() to convert the HTML into properly formatted plain text. We then calculate the Textbox size using a slightly larger font than needed as a way to ensure that the content of the RichText message will fit the box in most cases.
Once we know the size of the TextBox, we can easily resize the form to properly display the TextBox.
If there is too much text, we resize the form to its maximum permissible (70% of screen width and 90% of screen height) and change some of the visual cues to let the user know the text is overflowing.
One thing of note is the way the form is kept modal.
Rather than using DoCmd.OpenForm and DoCmd.Close I use the form as a class and create an instance manually (see the code in Dialog.Box and Dialog.Richbox). I keep this instance alive until I got the form’s result back.
If you are interested in knowing how the form is made modal, this is the code in FormDialog.ShowModal() what keeps the form open until the user clicks a button:
Public Function ShowModal() As VbMsgBoxResult
...
' Here we reset the result for the clicked button such as vbOK, vbYes, etc
' This is set in each Button's Click event
m_Result = -1
' Wait for the user to click a button
Do While (m_Result = -1)
DoEvents
Sleep 50
Loop
ShowModal = m_Result
End Function
The Sleep() function is a Win32 API that stops the current process for the given number of milliseconds. This in effects hands back the control to the Operating System for a short time. That way the system is still responsive and does not consume resources when it’s just waiting for user input.
Replacing MsgBox in existing code
As I said above, replacing the standard MsgBox is easy but you need to make sure your search and replace parameters are configured correctly:
If you’re getting strange compile errors, it may be because you forgot to tick the Find Whole Word Only and some of the strings containing the letter sequence “msgbox” were replaced in the process.
If that’s the case, you can revert the damage by simply doing a search and replace across the whole project on:
– VbboxStyle or VbDialog.BoxStyle to be replaced with VbMsgBoxStyle
– VbboxResult or VbDialog.BoxResultto be replaced with VbMsgBoxResult
Upgrading from an older version
If you are already using the enhanced DialogBox, upgrading to the newest version is simple.
In your Access application:
- delete the
FormDialog form,
- delete the
Dialog module.
- delete the
API_GetTextMetrics module if you have it (used in versions before 1.5)
Download the new version of the demo database below and open it.
- drag and drop the `FormDialog to your application
- drag and drop the
Dialog module to your application
That’s all you need to do.
Code and demo database
You can download a database containing all the necessary code as well as a number of tests.
This version contains the database in Microsoft Access accdb format (the code relies on features that don’t exist in pre-2007 versions of Access).
Download the EnhancedMsgBoxv1.10.zip (177KB), version 1.10 – 21OCT2014 containing the ACCDB database.
Code Updates
v1.10: 21OCT2014
Corrected minor bugs and added new features:
- Added
dialog.EscPath() to escape paths in your message and display them correctly, as suggested by Mark Singer in comment 115.
- Added option
NoStrEsc to display raw text when you don’t want escape and unicode sequences like ‘\n’ and ‘\u20ac’ to be converted at all in your whole message.
- Modified the code for
FileExists() to avoid the issue raised by Matthias Kläy in comment 116
- Added option
DismissID to allow the user to choose to prevent a message from displaying again (suggested by David Dewick in comment 110).
v1.9: 03FEB2014
Corrected some bugs and added some options:
- Corrected bugs that would throw exceptions when a message would contain some
file path whose ‘\’ would be wrongly interpreted as an escape sequence.
- Added options to show the buttons for copying the message to the clipboard
or saving it to file.
v1.8: 28SEP2013
Resolved some Unicode-related bugs:
- Corrected bugs that would truncate the strings in the dialog box when they contain some Unicode characters.
- Corrected bug with copy-to-clipboard that was not copying Unicode text.
- Corrected bug with copy-to-file that was not saving Unicode text properly.
v1.7: 13SEP2013
Added support for character literals in strings and Unicode escape sequences as supported in .Net strings.
See using .Net strings in VBA for fun an profit for details.
v1.6: 29JUN2013
Corrected issues pointed out by Joseph Strickland (thanks) when running under
Office 2010 x64.
Code updated and tested under a Virtual Machine running Win8 x64 and Office 2010 x64.
v1.5: 23JUN2013
Many thanks to contributors Steve Spiller, Jiriki and Kytu for improving and
pointing out issues. See details below.
- Moved the code from the API_GetTextMetrics module into the FormDialog class
to reduce the number of necessary files (now only FormDialog and Dialog objects
are necessary).
- Corrected bugs on the test form (button delay and beep options on the form
were not wired up correctly in the test form)
- RichBox was not initialising its buttonDelay correctly, resulting in the first
call to use a 0 delay instead of the DefaultButtonDelay value.
- Corrected bug reported by Jiriki on 06JUN2013 (when the ButtonDelay was set
to 0, the dialog would just close the first time the dialog was opened).
- Focus issues should be solved: the buttons are now properly focused and will
behave as the standard dialog box (you can hit ENTER or ESC on the keyboard
once the buttons are visible to confirm the default dialog action or cancel
it).
- Addressed parent form focus issue mentioned by KyTu on 19JUN2013: when closing
the dialog, the parent form will be properly focused instead of the Navigation
Panel.
- Now supports both x86 and x64 Office systems (32 and 64 bits versions of
MSAccess). Many thanks to Steve Spiller for sending me the updated database.
v1.4: 01APR2013
It’s been a while, but at last some improvements and bug fixes!
- As per Julie B’s comment, updated code to properly display the dialog on the proper monitor in multi-monitor environments.
The dialog box will open in front of the Access window that currently has focus (assumed to be the one that opened the dialog), so if your application has forms on different monitors, the dialog should open on the right one. If we can’t determine the active window, the dialog box will open in the middle of the monitor containing the main Access application window.
- Implemented Kristjan’s suggestion regarding the use of custom button labels. See updated description above.
- Corrected background colours for the dialog box so they correctly match the MS Office theme.
- Corrected a bug in the code that decided of the correct sound to play.
v1.3: 17MAR2009
Thanks to Henry of Access-Pro.de for proposing a correction to the default buttons behaviour.
- Updated behaviour for the default buttons. They are now focused in a way that matches that of the standard msgbox.
- Reversed the naming of the buttons on the form to make it a bit more consistent with the standard box.
v1.2: 07SEP2008
Thanks to Andy Colonna (http://www.pcesoft.com) for uncovering the following bugs (check out his free Spell Checker with source code!):
- Corrected bug in
Form_FormDialog.FilenameSanitize() function that would
fail to remove all invalid characters for a file name.
- File name for the saved text message will be truncated to first 32 characters
of message box title in
Form_FormDialog.MakeFriendlyFileName().
- Changed the use of
FollowHyperlink to ShellExecute to avoid security warning
in some instances in Form_FormDialog.btCopyToFile_Click()
- Corrected twips to pixel conversion bug in
API_GetTextMetrics.fTextWidthOrHeight() that
would result in an improperly sized dialog box when the text message was too
wide.
v1.1: 08AUG2008
- Corrected code for
DefaultButtonDelay (thanks to Geoffrey) (was referencing
wrong variable, causing self-referencing code).
- Corrected code for
Box and RichBox to take the DefaultSavedTextFileFolder
into account (the path was previously not passed onto the dialog boxes and
the text file would always be created in the application folder instead of
the one specified by DefaultSavedTextFileFolder)
- Added license notice at top of source code.
v1.0: 20MAY2008
Resources
This work is licensed under a Creative Commons Attribution 3.0 Unported License.
Free for re-use in any application or tutorial providing clear credit is made about the origin of the code and a link to this site is prominently displayed where end-users can easily access it.
May 20th, 2008
In my previous article about changing the MS Access colour scheme I had the need to allow the user to restart the database after the colour scheme was changed.
(Article and Code Updated 13FEB2009.)
Being able to cleanly restart and compact the application is also useful in other instances:
- Changes made to the environment
- Recovering from errors (for instance after a network disconnection)
- Forcing the user to re-log cleanly into the application
- Automatically restarting a long-running application (for instance so that it may automatically compact on close and restart afresh with or without user intervention).
The problem is that you cannot -to the best of my knowledge- close and open again the same database from within MS Access itself.
Most executables cannot do that and the way to solve the issue is usually to pass the control to another boostrap programme, close the main application and let the bootstrap programme re-open the main application again.
I wanted a simple and clean way of using it. One that would not require shipping external dependencies.
How to use it
Download the sample database below, copy the Utilities module or just the Restart sub defined in it into your own application.
To use it, just call the Restart sub and the application will close and re-open.
If you supply the optional Compact:=true parameter, the database will also be compacted during the restart process.
This will work for normal databases (mdb/accdb) and also compiled (mde/accde) and runtime (accdr) databases as well.
Important note
If you want to use this code do not enable the Compact on Close option in Access for your database as the code doesn’t pick that up yet.
Instead, you can either simply call restart Compact:=true on user action (for instance from a menu) or on other triggers, for instance when the database is being open and hasn’t been compacted for more than a week.
How it works
If you’re curious about the technical details, here is how it was put together.
The main idea is that the MS Access database application has to be self-sufficient and restart itself by performing these steps:
- create a small batch file
- run the batch file, passing the path and extension of our database
- close the main application
- the running batch file would wait for the MS Access lock file to be removed
- once the lock file disappears, we open the database after compacting it if required.
The key point here is that the batch file cannot just reopen the database right away: if the application is big or if it’s compacting on close for instance, it may take several seconds to actually close.
The only moment we can be pretty sure that the database is effectively closed is when the lock file is deleted by MS Access.
The batch file is hard-wired in the Restart sub that does all the work:
SETLOCAL ENABLEDELAYEDEXPANSION
SET /a counter=0
:CHECKLOCKFILE
ping 0.0.0.255 -n 1 -w 100 > nul
SET /a counter+=1
IF "!counter!"=="60" GOTO CLEANUP
IF EXIST "%~f2.%4" GOTO CHECKLOCKFILE
"%~f1" "%~f2.%3" /compact
start " " "%~f2.%3"
:CLEANUP
del %0
When the application runs the batch file, it passes 4 arguments:
- the full path to the MSAccess.exe executable (used for compacting the database)
- the full path to the database without the extension
- the database file extension without the leading “.”
- the appropriate database lock file extension (
laccdb or ldb).
This allows us to easily construct the path to either the database or the lock file at line 07 and 09.
Line 08 is actually only inserted if we need to compact the database: it simply launches MSAccess.exe with the /compact command line switch.
The funny use of PING is actually a simple way to wait for some time before we check if the lock file is still there or not. There is no SLEEP or WAIT function provided by default in Windows so we have to be a bit creative and use the time-out option of the PING command trying to ping an nonexistent, but valid, IP address.
Once the lock file has disappeared, we open the database at line 09 and then delete the batch file itself so we leave no leftovers.
The other thing of note is that we now use a counter to keep track of the number of times we checked the existence of the lock file.
Once this counter reaches a pre-determined amount (60 by default, ~ 45 seconds) we consider that there is a problem and the database application didn’t close, so we just exit and delete the batch file.
Download the DatabaseRestart.zip (48KB) containing both an Access 2007 ACCDB and Access 2000 MDB test databases.
Other implementations
Code Updates
v1.2: 13FEB2009
- Added optional parameter to compact the database during restart.
v1.1: 09AUG2008
- Now a separate test database (used to be bundled with the Colour Scheme sample).
- Added support for older Access versions (an Access2000 MDB is now included).
- Corrected wrong lock file extension for accd* files.
- Added a time-out feature after which the batch file will delete itself
after a while if the Access lock file wasn’t released
(for instance following a crash).
- Added checks to delete the batch file if it has not deleted itself for some
reason (for instance after a reboot).
- The batch file now has a unique name based on the name of the database,
allowing multiple databases to be restarted from the same directory.
- Added license notice at top of source code.
- Updated the article to reflect the changes.
v1.0: 06MAY2008
This work is licensed under a Creative Commons Attribution 3.0 Unported License.
May 6th, 2008
Microsoft Office 2007/2010 comes with 3 colour (color) schemes.
Users can easily change it but when you deploy an Access application under the Runtime your users have no way to set the colour scheme as the application’s options are not available.
(Article and Code Updated 01DEC2014.)
Luckily for us, the global colour scheme setting in the registry under the Key:
- Office 2007:
HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Common\Theme
- Office 2010:
HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Common\Theme
- Office 2013:
HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Common\UI Theme
The values being stored under that key are, For Office 2007 and Office 2010:
- 1: Blue
- 2: Silver
- 3: Black
For Office 2013:
- 0: White
- 1: Light Gray
- 2: Dark Gray
With this information, we can easily both read and set the colour scheme.
The only caveat is that I could not find a way to notify Access to reload the setting automatically once it is changed, so users will have to restart the application before the change becomes active.
A small price to pay but if anyone has a better idea, please let me know.
To write the new value to the registry I use a set of WIN 32 APIs that are more flexible than the default ones provided in VBA.
You can download the sample database as it contains all necessary files, including the definition for the Win32 API functions.
Download the ColorSchemeV1.4.zip (46KB) containing the ACCDB database.
The sample also contains some code to restart the database. This is the subject of another post: Restarting and compacting the database programmatically.
Improvements/uses:
- Find a way for Access to reload the settings without having to restart the application.
- Use the knowledge about the current scheme to change the other colour settings in the application (or even adapt the form’s theme).
Updates:
v1.4: 01DEC2014
- Updated code for Office 2013 support.
- Updated Registry API functions for compatibility with 64 bit Office
- Combined all modules into OfficeScheme
- Added new function to return the name of a Theme/current Theme in plain English.
v1.3: 31MAY2011
- Updated code for Office 2010 support.
- Autodetect correct registry key for Office 2007/2010
v1.2: 13FEB2009
- Updated code for restarting the database.
See exact changes at: http://blog.nkadesign.com/2008/ms-access-restarting-the-database-programmatically/
v1.1: 09AUG2008
- Updated code for restarting the database.
See exact changes at: http://blog.nkadesign.com/2008/ms-access-restarting-the-database-programmatically/
- Added license notice to code.
v1.0: 03MAY2008
References:
May 3rd, 2008
Microsoft Access Team made an interesting post and a follow-up on how to add a transparent layer that cover the screen to focus the attention of the user to a login form or other important popup window.
The trick is to use some WIN 32 API calls to modify the transparency of a standard MS Access form made to cover the screen.
The effect is quite neat and I thought I would try it and make a sample database for others to tinker with it.
My version allows you to chose between covering the whole screen or just the main Access window and it will test if it’s running under a Remote Desktop Terminal and disable the layer in that case.
Update 07MAY2008
Following Rob’s improvements I made another sample database that incorporates his code with a few improvements:
- I added the
LightBoxForm.LayerToFullScreen property so users can choose explicitly how they want the layer to be shown.
- I moved the code to hide the layer into a Hide() sub so you can just show/hide the layer using
LightboxForm.Show and LightboxForm.Hide.
- I changed the Form’s
Resize event code in the LightBoxForm class to avoid flickering: resizing the form within its Resize event actually trigger the Resize event again a second time which causes flickering.
I simply modified the code to make the form totally transparent (opacity of 0) the first time the event is fired and assign it the expected opacity when the event handler in re-entered.
'-----------------------------------------------------------------------------
' Handle the Layer Form Resize event
'-----------------------------------------------------------------------------
Private Sub m_objForm_Resize()
Static busyResizing As Boolean
Dim lngStyle As Long
Dim r As RECT
' disable screen updates
m_objForm.Painting = False
' When the form opens initially, we make it totally transparent to avoid flickering
lngStyle = GetWindowLong(m_objForm.hWnd, GWL_EXSTYLE)
SetWindowLong m_objForm.hWnd, GWL_EXSTYLE, lngStyle Or WS_EX_LAYERED
SetLayeredWindowAttributes m_objForm.hWnd, 0, 0, LWA_ALPHA
' If the Access window is maximized, then maximize the lightbox form.
' If the Access window is not maximized, then
' position the lightbox form so that it covers the Access window
If IsZoomed(hWndAccessApp()) Or m_bLayerToFullScreen Then
DoCmd.Maximize
Else
GetWindowRect Application.hWndAccessApp(), r
MoveWindow m_objForm.hWnd, r.x1, r.y1, (r.x2 - r.x1), (r.y2 - r.y1), True
End If
If busyResizing Then
' Get the current window style, then set transparency
lngStyle = GetWindowLong(m_objForm.hWnd, GWL_EXSTYLE)
SetWindowLong m_objForm.hWnd, GWL_EXSTYLE, lngStyle Or WS_EX_LAYERED
SetLayeredWindowAttributes m_objForm.hWnd, 0, (m_sngOpacity * 255), LWA_ALPHA
' enable screen updates
m_objForm.Painting = True
' Back to normal
busyResizing = False
Else
busyResizing = True
End If
End Sub
Samples
There are now 2 sample databases. Ech zip contains a Microsoft Access 2007 ACCDB file and its conversion to Access 20001 and Access 2002-2003 MDB but please note that I have not been been able to test those in older version of Access and that form transparency doesn’t work in Operating Systems older than Windows 2000.
Download TransparentLayer02b.zip (138KB), recommended version
(improved, more flexible version, based on Rob’s updated article).
Download TransparentLayer01b.zip (122KB), original version
(simple code, based Rob’s original article).
Troubleshooting
- If you are getting security warnings: make sure that you open the database from a Trusted Location or you will receive a security prompt.
If you don’t know how to do that, check these steps.
- If the layer appears on top of the login form instead of behind: make sure that the top-most form has ist
Modal properties set to Yes and the frmLightBox form has its modal property set to No.
If you improve on it, please let me know and I’ll post it here for all to find.
May 1st, 2008
Microsoft SQL Server comes in many editions, ranging from completely free to use and distribute to versions costing tens of thousands of dollars.
For small businesses, or when you can live with the limits imposed, the Express edition is one option to consider.
Here are some reasons why SQL Server Express may be a good choice:
You’re upsizing an Access database
SQL Server is the natural extension of upsizing an existing Access database. It work automagically with minimum effort providing that you followed some simple good-design rules from the start.
You’re future-proofing your needs
Because SQL Server comes in many flavours, you know you -or your customers- can upgrade to a more capable (albeit more expensive) version in the future if needed.
Very flexible
As usual with a lot of Microsoft development tools, SQL Server will happily let you shoot yourself in the foot by providing you with a fairly easy way to treat your database as a complete development platform.
It’s good in the sense that you have interesting tools and capabilities included in the server, and it’s bad for the exact same reasons.
I tend to prefer database servers to be just that: data repositories, and I’m not too fond of relying on specific, non-standard features of a particular database system, but what do I know.
Excellent out-of-the-box development support
Deep integration with .Net and Visual Studio, without any effort, Microsoft saw to that of course.
In some cases, such as LINQ to SQL, it’s almost the only real choice, although the other database vendors are working hard at the necessary providers, so that lead should be short-lived.
There is something to be said about developer productivity: you have to give credit to Microsoft for making their tools well integrated and usable from each-other. What it means is that for small developer shops there is much to gain in surrendering to this “ease of the default”.
Of course, it’s a double-edged sword, but having a complete development infrastructure work out of the box is certainly a big help, and if you don’t like it, you’re still free to chose something else.
Lots of tools
With SQL Server Advanced Services, you also get Server Management and Reporting Services. These are great tools made available for free.
The only missing one for SQL Server is the Reporting designer. While the reporting service means that you can use existing reports, only SQL Server Standard and Enterprise have it.
There is an option for developers though: the (nearly free) SQL Server Developer edition is in fact the same as SQL Server Enterprise, without the license to use in non-developer or tester environment. This means that as a developer, you can create and distribute your reports to be used by your customers who will be using SQL Server Express.
Did I mention it’s free?
All this is free, as in beer, not as in liberty though.
For commercial applications targeted at small businesses, SQL Server Express is a really good choice: you can distribute it without problem, the customer gets all the tools, can easily find outside support, and they can always migrate to a more beefy version if their needs grow, all that without having to depend on you.
So it sort of offers customers a kind of freedom that they wouldn’t have with other choices.
Of course you can get that with other database systems, although you have to be careful which Open Source one you choose: I recently decided not to use MySQL any longer for the simple reason that it’s too expensive and restrictive in a business environment, at least for the kind of work I do.
Why would you not want to use SQL Server Express?
You don’t want to depend on Microsoft
That can be a good reason enough sometimes. There is nothing preventing Microsoft from crippling SQL Server Express in the future to force users to move to a paying version early.
I suppose that whatever database system you use, even Open Source ones, there is always the possibility that the company supporting its development goes bankrupt, the Open Source projects goes dead or decides to go in a direction that doesn’t suit you..
It’s only supported on Microsoft OS
True, and that’s a good reason to chose something else.
There is a hidden cost in SQL Server Express: it needs to run on a Windows machine, and that’s not free, although SQL Server will work on older Windows 2000 machines and Windows XP which are arguably not expensive.
Your database needs will exceed SQL Server Express specifications
If you think any of your databases will grow beyond 4GB or that it will get busy and you need all the RAM and CPU you can get, then SQL Server Express is probably not for you as it will only use 1 CPU and 1GB of RAM at most.
If your needs go beyond that, then you’ll have to move to a paying version.
Upgrading can be expensive
It’s true that moving to the next cheapest upgrade of SQL Server Workgroup will cost you about US$700 for a 5 user license. The limits imposed on the database are much higher (2 processors, 3GB RAM and no size limit) but if you need more clients / or higher limits, then the expense will grow quite fast, and you’ll have to manage those hateful client access licenses.
Your needs are more modest
We haven’t talked here about single-file/single-user database systems.
These databases don’t user resident services and are usually meant for more limited needs, sometimes allowing only a single user to be connected.
The footprint of these non-server databases is a lot smaller, typically only requiring a single dll or a handful of files to be installed.
They are extremely useful for desktop application that do not really require multi-user support or advanced security features.
Here again, Microsoft offers SQL Server Compact, which, despite the name, doesn’t have much to do with the other SQL Server editions. This one is also free, but has a limited feature set and only allow single-user access as it is meant to be a lightweight database and works well in limited memory environments such as those found on mobile devices.
Of course, here again there is a lot of competition: Thunderbird, SQLite, MS Access and VistaDB (for embedding into .Net applications, not free) to name a few.
These are pretty good times when it comes to databases: we get more choices now than we ever had.
As usual, choosing a database as a back-end for your products isn’t easy: you need to consider cost, licensing, support and the future.
There isn’t a single database system that will meet everyone’s needs for all types of use, so choose carefully.
SQL Server Express is a very good contender in that market. It should not be dismissed out of hand because it’s from Microsoft, in the same way that PostgreSQL shouldn’t be dismissed because it’s Open Source.
Just use the tool that best answers your needs for your particular circumstances.
References:
January 30th, 2008
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