BUG: Some Property Values May Be Incorrect in Maximized Form (79242)
The information in this article applies to:
- Microsoft Visual Basic Professional Edition for Windows 2.0
- Microsoft Visual Basic Professional Edition for Windows 3.0
- Microsoft Visual Basic Standard Edition for Windows 1.0
- Microsoft Visual Basic Standard Edition for Windows 2.0
- Microsoft Visual Basic Standard Edition for Windows 3.0
- Microsoft Windows 3.0
- Microsoft Windows 3.1
This article was previously published under Q79242 SYMPTOMS
The Top, Left, ScaleHeight, and ScaleWidth properties of a maximized
Visual Basic for Windows form may return incorrect values. When a form
is maximized, the values returned by these properties should be close to
the resolution of your monitor. The only difference between the
property values returned and the resolution should be due to
BorderStyles, menus, or title bars, and should in no case be greater
than the resolution of your monitor.
CAUSE
In some cases, with a maximized form, the returned property values can
be greater than the screen resolution. This is because of a problem in
the Windows API routine, GetClientRect(), which Visual Basic calls to
get the form properties. This is a problem with Microsoft Windows
versions 3.0 and 3.1, not with Visual Basic.
STATUS
Microsoft has confirmed this to be a bug in Microsoft Windows versions
3.0 and 3.1. We are researching this problem and will post new
information here in the Microsoft Knowledge Base as it becomes available.
MORE INFORMATION
The Left property determines the distance between the internal left edge of
an object and the left edge of its container. The Top property determines
the distance between the internal top edge of an object and the top edge
of its container. ScaleHeight sets or returns the range of the vertical
axis for an object's internal coordinate system, and ScaleWidth sets or
returns the horizontal axis. On a form, the coordinate system includes the
form's internal area, not including borders and title bar.
Steps to Reproduce Problem
To duplicate the problem, experiment with various BorderStyles, set
ScaleMode to pixels, and add the following code:
Sub Form_Click()
Print Left,Top,ScaleWidth,ScaleHeight
End Sub
Run the application and click the form. Note the values printed. With no
border, the values should correspond to the resolution of your monitor,
and should change slightly for each BorderStyle from the addition of
borders, menus, and title bars.
Here's another example. This occurs when you use the following code in a
maximized form with a ScaleMode of 1 (twips) in a 800-by-600 (pixel)
screen resolution:
Sub Form_Click
Print "Screen = "; screen.width; ", "; screen.height
' Enter each Print statements on one, single line.
Print "Form = "; form1.width; ", "; form1.height;
" at "; form1.left; ", "; form1.top
Print "-------------------------------------------------------
------------------------"
End Sub
The following is the results:
Screen = 12000, 9000
Form = 12120, 9120 at -60, -60
| Modification Type: | Major | Last Reviewed: | 12/12/2003 |
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| Keywords: | kbbug KB79242 |
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