Microsoft KB Archive/168829

= How To Get a Hierarchical List of Window Names and Classes =

Article ID: 168829

Article Last Modified on 2/12/2007

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APPLIES TO


 * Microsoft Visual Basic 6.0 Learning Edition
 * Microsoft Visual Basic 6.0 Professional Edition
 * Microsoft Visual Basic 6.0 Enterprise Edition
 * Microsoft Visual Basic 5.0 Control Creation Edition
 * Microsoft Visual Basic 5.0 Learning Edition
 * Microsoft Visual Basic 5.0 Professional Edition
 * Microsoft Visual Basic 5.0 Enterprise Edition
 * Microsoft Visual Basic 4.0 Standard Edition
 * Microsoft Visual Basic 4.0 Professional Edition
 * Microsoft Visual Basic 4.0 32-Bit Enterprise Edition
 * Microsoft Access 95 Standard Edition
 * Microsoft Access 97 Standard Edition

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This article was previously published under Q168829



SUMMARY
When trying to determine whether a child window of an application is open, you need to know whether it is a child of the main application window, a grandchild, or an independent window. This article provides a method of creating a hierarchical listing of all currently open windows and their window class names, making it easier navigating a program's window hierarchy.



MORE INFORMATION
WARNING: Microsoft provides code examples for illustration only, without warranty either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose. This code is provided 'as is' and Microsoft does not guarantee that the following code can be used in all situations. Microsoft does not support modifications of the code to suit customer requirements for a particular purpose.

Step-by-Step Example
 Create a new project with a Form and a Module.  Add the following controls to the form:   Control            Name         Property   Value Command button    Command1 Text box          Text1        MultiLine  TRUE Text box          Text1        Scrollbars 2- Vertical

NOTE: The MultiLine property only applies to Visual Basic.   Type the following code into the module: Option Explicit

Public Const GW_CHILD = 5 Public Const GW_HWNDNEXT = 2

Declare Function GetWindow Lib "user32" (ByVal hwnd As Long, _             ByVal wCmd As Long) As Long Declare Function GetWindowText Lib "user32" Alias "GetWindowTextA" _ (ByVal hwnd As Long, ByVal lpString As String, _             ByVal cch As Long) As Long Declare Function GetTopWindow Lib "user32" _ (ByVal hwnd As Long) As Long Declare Function GetClassName Lib "user32" Alias "GetClassNameA" _ (ByVal hwnd As Long, ByVal lpClassName As String, _             ByVal nMaxCount As Long) As Long

  Add the following code to the form's module: Sub AddChildWindows(ByVal hwndParent As Long, ByVal Level As Long) Dim WT As String, CN As String, Length As Long, hwnd As Long If Level = 0 Then hwnd = hwndParent Else hwnd = GetWindow(hwndParent, GW_CHILD) End If       Do While hwnd <> 0 WT = Space(256) Length = GetWindowText(hwnd, WT, 255) WT = Left$(WT, Length) CN = Space(256) Length = GetClassName(hwnd, CN, 255) CN = Left$(CN, Length) Me!Text1 = Me!Text1 & vbCrLf & String(2 * Level, ".") _ & WT & " (" & CN & ")" AddChildWindows hwnd, Level + 1 hwnd = GetWindow(hwnd, GW_HWNDNEXT) Loop End Sub

Sub Command1_Click Dim hwnd As Long hwnd = GetTopWindow(0) If hwnd <> 0 Then AddChildWindows hwnd, 0 End If     End Sub

 Visual Basic only: Run the project.

Access only: Open the form.  Click the CommandButton. The text box will be filled with a list of windows and their children arranged in a hierarchical order. The class name will follow the window name, such as: <pre class="fixed_text">     MainWindowName (WindowClass) ..ChildWindowName (WindowClass) ....GrandchildWindowName (WindowClass)

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NOTE: Not all windows will have a name but all will have a Window Class.

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