Windows API Guide: DOCINFO Structure

Declare Function EnumPropsEx Lib "user32.dll" Alias "EnumPropsExA" (ByVal hWnd As Long, ByVal lpEnumFunc As Long, ByVal lParam As Long) As Long

Platforms

Windows 95: Supported.
Windows 98: Supported.
Windows NT: Requires Windows NT 3.1 or later.
Windows 2000: Supported.
Windows CE: Not Supported.

Description & Usage

EnumPropsEx enumerates all of the window properties of a window. Information about each property is passed, one at a time, to the specified callback function. The window properties are not enumerated in any particular order.

Return Value

If the window had no window properties set, the function returns -1. Otherwise, the function returns whatever the most recent value the callback function returned was.

Visual Basic-Specific Issues

None.

Parameters

hWnd: A handle to the window to enumerate the window properties of.
lpEnumFunc: A pointer to the PropEnumProcEx callback function which receives information about each enumerated window property.
lParam: An additional value to pass to the function specified by lpEnumFunc.

Example

' This code is licensed according to the terms and conditions listed here. ' List the names of each window property belonging to window ' Form1.  This example does not display the actual data in the properties ' because the callback function is not told what the handle for each ' property refers to. ' *** Place the following code in a module. *** ' This callback function merely displays the name of the window property ' it is given. Public Function PropEnumProcEx(ByVal hwnd As Long, ByVal lpszString As Long, ByVal hData As Long, ByVal dwData As Long) As Long   Dim propname As String  ' receives the name of the window property   Dim retval As Long  ' generic return value   ' Copy the string pointed to by lpString into a "real" string.   propname = Space(lstrlen(lpszString))   retval = lstrcpy(propname, lpszString)   ' Display the property name (not including its value).   Debug.Print "- "; propname   ' Tell EnumPropsEx to continue enumeration.   PropEnumProcEx = 1 End Function ' *** Place the following code wherever you wish to enumerate the properties. Dim retval As Long  ' result of enumeration Debug.Print "BEGINNING ENUMERATION OF Form1's PROPERTIES" ' Enumerate the properties of window Form1. retval = EnumPropsEx(Form1.hWnd, AddressOf PropEnumProcEx, 0) If retval = -1 Then  ' no properties to enumerate   Debug.Print "(no window properties were found)" End If