Microsoft KB Archive/195631

= PRB: Effects of Operating System Version On TextBox Alignment =

Article ID: 195631

Article Last Modified on 5/12/2003

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APPLIES TO


 * Microsoft Visual Basic 6.0 Learning Edition
 * Microsoft Visual Basic 5.0 Learning Edition
 * Microsoft Visual Basic 6.0 Professional Edition
 * Microsoft Visual Basic 5.0 Professional Edition
 * Microsoft Visual Basic 6.0 Enterprise Edition
 * Microsoft Visual Basic 5.0 Enterprise Edition
 * Microsoft Visual Basic 5.0 Control Creation Edition

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This article was previously published under Q195631



SYMPTOMS
The value of the "Alignment" property of a TextBox control is ignored and the default of "left aligned" is applied on some systems. The same application installed on other systems does not exhibit this behavior.



CAUSE
Visual Basic derives its TextBox control from a proprietary class called "ThunderTextBox," which in turn is based on the "Edit" class provided by the operating system. Because the operating system defines the "Edit" class, some of the properties and functionality of a TextBox may change depending upon the version of the operating system where the application is executed. This is the case with the TextBox's Alignment property. In earlier versions of Windows, changes to the "Alignment" property would not take effect unless the "MultiLine" property of the TextBox was set to "True." The latest versions of the Windows operating system no longer have this limitation.

Any control from any development environment that is derived from the "Edit" class will demonstrate the same change in behavior.

Versions of Windows that require the "MultiLine" property to be set to "True" in order for the "Alignment" property to take effect include:

Windows 95 (regardless of service packs)

Windows NT 3.51 (regardless of service packs)

Windows NT 4.0

Windows NT 4.0 with Service Packs 1 or 2

Versions of Windows that do not have this requirement include:

Windows 98

Windows Me

Windows NT 4.0 with Service Pack 3 or higher



RESOLUTION
There are two approaches for working around this inconsistency:


 * Assume the older operating system limitation is being enforced and set the TextBox control's "MultiLine" property to "True."
 * Use multiple overlapping TextBox controls and vary which one is visible depending on the operating system in use (checked via API) and the alignment desired.



STATUS
This behavior is by design.

