DOCUMENT:Q152136  07-SEP-2001  [vbwin]
TITLE   :HOWTO: Know if Large/Small Font Is in Use Under Win95/98/Me/NT
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER::4.0,5.0,6.0
OPER/SYS:
KEYWORDS:kbprint kbAPI kbPrinting kbSDKWin32 kbVBp kbVBp400 kbVBp500 kbVBp600 kbGrpDSVB kbDSuppo

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The information in this article applies to:

 - Microsoft Visual Basic Learning Edition for Windows, versions 6.0, 5.0 
 - Microsoft Visual Basic Professional Edition for Windows, versions 6.0, 5.0 
 - Microsoft Visual Basic Enterprise Edition for Windows, versions 6.0, 5.0 
 - Microsoft Visual Basic Control Creation Edition for Windows, version 5.0 
 - Microsoft Visual Basic Standard Edition, 32-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0 
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SUMMARY
=======

Determining whether Windows 95, Windows 98, Windows Me, or Windows NT 3.51 is
using large or small fonts can be done from Visual Basic through Windows API
calls. The API that retrieves information about the physical font selected for a
device context is GetTextMetrics().

MORE INFORMATION
================

The theory of determining whether a large or small font is used under Windows
95, Windows 98, Windows Me, or Windows NT 3.51 is based on the assumption that
the Windows display driver uses the default value VGASYS.FON for Small Fonts and
8514SYS.FON for Large Fonts. If the user changes the default system font
manually to any other value, this theory will not apply.

Step-by-Step Example
--------------------

1. Get the handle of the Desktop window.

2. Get the Device Context for the entire Desktop window (including borders,
   scroll bars, captions, menus, and so on).

3. Set the mapping mode to pixels.

4. Get the size of the system font.

5. Reset the mapping mode to its original setting.

6. Release the device context obtained through a call to GetWindowDC.

If the system font is more than 16 pixels high, then large fonts are being used.

Sample Code
-----------

      '** TYPES **
      Type TEXTMETRIC
        tmHeight As Integer
        tmAscent As Integer
        tmDescent As Integer
        tmInternalLeading As Integer
        tmExternalLeading As Integer
        tmAveCharWidth As Integer
        tmMaxCharWidth As Integer
        tmWeight As Integer
        tmItalic As String * 1
        tmUnderlined As String * 1
        tmStruckOut As String * 1
        tmFirstChar As String * 1
        tmLastChar As String * 1
        tmDefaultChar As String * 1
        tmBreakChar As String * 1
        tmPitchAndFamily As String * 1
        tmCharSet As String * 1
        tmOverhang As Integer
        tmDigitizedAspectX As Integer
        tmDigitizedAspectY As Integer
      End Type

      '** Win32 API DECLARATIONS **
      Declare Function GetTextMetrics Lib "gdi32" Alias "GetTextMetricsA" _
       (ByVal hdc As Long, lpMetrics As TEXTMETRIC) As Long
      Declare Function GetDesktopWindow Lib "user32" () As Long
      Declare Function GetWindowDC Lib "user32" (ByVal hwnd As Long) As Long
      Declare Function ReleaseDC Lib "user32" (ByVal hwnd As Long, ByVal hdc _
       As Long) As Long
      Declare Function SetMapMode Lib "gdi32" (ByVal hdc As Long, ByVal _
      nMapMode As Long) As Long

      '** CONSTANTS **
      Global Const MM_TEXT = 1

      '** Function **
      Public Function gbl_GetFontRes$()
      Dim hdc, hwnd, PrevMapMode As Long
      Dim tm As TEXTMETRIC

        ' Set the default return value to small fonts
        gbl_GetFontRes$ = "VGA"

        ' Get the handle of the desktop window
        hwnd = GetDesktopWindow()

        ' Get the device context for the desktop
        hdc = GetWindowDC(hwnd)
        If hdc Then
          ' Set the mapping mode to pixels
          PrevMapMode = SetMapMode(hdc, MM_TEXT)

          ' Get the size of the system font
          GetTextMetrics hdc, tm

          ' Set the mapping mode back to what it was
          PrevMapMode = SetMapMode(hdc, PrevMapMode)

          ' Release the device context
          ReleaseDC hwnd, hdc

          ' If the system font is more than 16 pixels high,
          ' then large fonts are being used
          If tm.tmHeight > 16 Then gbl_GetFontRes$ = "8514"
        End If

      End Function

Additional query words:

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Keywords          : kbprint kbAPI kbPrinting kbSDKWin32 kbVBp kbVBp400 kbVBp500 kbVBp600 kbGrpDSVB kbDSupport 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500Search kbVB500 kbVB600 kbVB400Search kbVB400 kbZNotKeyword3
Version           : :4.0,5.0,6.0
Issue type        : kbhowto

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