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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
Sometimes a runtime error only manifests itself after an EXE ismade and not in debug mode. This can be hard to track down, evenwith message-box statements. Use the code profiler
I like to use the Constant.txt file Microsoft has been kind enoughto provide. For a new project, copy Constant.txt to a new filesuch as MyConst.txt. Place MyConst.txt in the same
This code will prevent a beep when you hit [ENTER] or [TAB] ina text box whose maximum character limit has been reached: Sub Form_KeyPress (keyascii As Integer)’Eliminate beep if {ENTER}
In VB4 the TypeOf statement works with any valid object type,not just forms and controls. This allows you to pass objects ofdifferent classes to the same procedure for a class-specific
Here is a tip to help with missing or mispositioned text. Thisfailing code works fine with VB3: ClsPrint Spc(10); “Enter Your Name”;currentx = 0currenty = currenty + 1Print Spc(10); “Enter
A tip on page 48 of the March 1996 issue of VBPJ statesthat an ODBC error message occurs when using VB3 with the Access2.0 compatibility layer. An error occurs if
It is well known that VB3 is not always as conscientious as itshould be about unloading all the forms in an application whentheapplication terminates. Because unloading all the forms for
Just before performing your final ‘make EXE,’ switch your desktopcolor scheme and see just how many backgrounds you have hard-coded!(Sadly, several excellent shareware controls fail here, VBPJcontributors are guilty of
The Lost_Focus and Got_Focus events are the most-used events for implementing validation and texthighlighting. Wouldn’t it be nice to respond instantly to these events and to do it from a
Set the AutoRedraw property to True and the benefits and trade-offsinclude much faster repaints and some wasted memory. If your formis resizable, you waste a lot of memory, because the
Visual Basic doesn’t have a procedure like the DLookUp function that Access has. You can use thisprocedure in VB to receive the Name of an object by ID: Public Function
The ElasticForm subroutine, part of CodeBank’s standard procedurelibrary, automatically repositions and sizes all controls on anSDI form when the user or code resizes the form. To use the routine,simply lay
Because MDI forms don’t have a border property, the user can drag the borders and distort the size of theMDI form. If the user tries to resize the form, I
Ever wished you could use the Save parameter outside of a Validate event? Have you noticed that if abound control is changed and you set DataChanged back to False, Save
This tip has been published more than once on pages of VBPJ(See “99 of the Hottest Tech Tips For VB Developers,”Supplement to the February 1996 issue of VBPJ, page 17).This
Much of the ease of use of Windows 95 comes from the fact thatits user interface objects have their own context menus, whichcan be accessed through a simple right-click of
While we are speaking of SendMessage, there is another trick youmay find interesting enough to include in your programming habits.When used with some particular messages, the lParam argument isreally considered
I was surprised to learn that the SWAP command was not implementedin Visual Basic when I read a letter in the February 1996 issueof VBPJ requesting that Microsoft bring to
Are your programs not executing instructions in VB4 that wereexecuting in VB3? Try this in Qbasic, VB3, and VB4: BEEP: BEEP: BEEP If you F8-step through this very complex code,
Most programmers want their applications to look like commercial software, so they want to add their ownhelp files. How do you open the contents of a Windows help file in