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Use With…End With to minimize the number of repeated OLE lookups.This has the added advantage of not requiring the temporary substitutionobject.
Place one label on your form, tailor its properties (such as left-alignand autosize), and copy and paste it to create the rest of your labels.
Start the in-process OLE server using a Sub Main procedure. Includeall server initialization code in the Sub Main procedure. Don’t show formsfrom the Sub Main procedure and don’t use the
VB developers that program with C language might be confused by a feature in the language. Consider thiscode: Dim x As IntegerDim y As IntegerDim z As Integer x =
Do set all object variables to nothing before ending the application.When the End statement is executed in the OLE client application, the OLEserver is shut down and the Terminate events
Don’t display errors from the OLE server. Instead, raise an error tothe client application. Use error numbers greater than vbObjectError +512 and less than vbObjectError + 5535. Values between vbObjectError
Often when using Transact-SQL, I want to capture comments from a user in a text box and send them tothe database. However, if the user types an apostrophe in the
I design VB applications for approximately 300 employees in a networked environment. It’s difficult to keepthose PCs up to date with the most current version of an app, so I
Use this algorithm to swap two integer variables: a = a Xor b b = a Xor b a = a Xor b
Place this code in the declaration section of a module: Public Sub Win95Shrivel(xForm As Form) ‘ Sets the form’s window status to ‘ minimized xForm.WindowState = 1End Sub Call it
When an image list is referenced by another object such as a toolbar, you can only add images to the imagelist. VB doesn’t allow deletes or changes to the size
I was developing a CGI application that read a database and pieced together the fields into a string forrepresentation as an HTML form. The surprise came when I found how
Code portability is extremely important, especially now that VBA is available in so many products. Someproblems might occur if you want to use VB4 or VB5 code in Access 8
Document the interface for your OLE server by using the Options buttonin the Object Browser. To provide more full-featured documentation, usea help file. Use the Object Browser to tie the
Pass as much data to and from the OLE server as possible in each call.Data transfer is fast, but calling is slow, especially with out-of-processservers. For example, you could pass
Don’t provide a method that terminates your server. Let the server automaticallyterminate when no references to the server exist. If you provide an Exitmenu option in an OLE server that
Test an in-process OLE server DLL by building it first as an out-of-processserver. This makes it possible to debug and test. Also, the stability ofthe entire application will be affected
The well-known Horner schema lets you calculate polynomial expressions efficiently. To calculate: A*x^N + B*x^(N-1) + . + Y*x + Z ( ^ means power ), simply write this expression
You can easily make a group of controls visible or invisible. At design time, select all controls you want tomake visible or invisible during the execution. Press F4, and assign
I often want to get to the General code section of a form quickly, either to hack module-level variables or tograb the procedure pull-down to find that function whose name
Do you sometimes need to format rounded numbers to a specific number of digits? You can accomplish thisin one step: n = 12.345Format(n, “0.00”)’returns “12.350”Format(n, “0.”)’returns “12.00”Format(0.55, “#.0”) ‘returns “.60”
If you set a form’s ControlBox property to False, the Minimize and Maximize buttons also become invisible.Suppose you want to provide functionality to the user to maximize and minimize the
Copy (Ctrl+C) and Paste (Crtl+V) functions are already includedin a text-box control, but what if you want to avoid these functions?You might suppose that you can handle Ctrl key combinations
Often, to create status-bar help, you place code in the mouse-moveevent procedures of controls to place text describing the controlon the status bar. Every time you update the text property,
If you need to analyze the performance of a Jet 3.0 query by thequery execution plan, you may do so by adding this registry keyand running regedit: \HKEY_LOCAL_MACHINESOFTWARE\_ MicrosoftJet3.0EnginesDebug For
In the “Determine the Class of YourObject with the TypeOfStatement” tip, the Desk and House objects have many propertiesin common. Instead of duplicating code by having a separate Printmethod for
vGive your ListView control in report view the sort functionalityof the Win95 Explorer. This code will allow you to sort by anycolumn. If your list is already sorted by the
Be aware that when using the Path property of the Applicationobject (App.Path), if your EXE is run from the root directoryof a drive, App.Path will return the drive letter and
Sometimes it is desirable to prevent a user from moving a form.A little known feature of Windows is that for any form, functionalitythat doesn’t appear in the control menu (ControlBox