Windows API Guide - Reference - Volume 1: Version 3.0 For the MS-DOS and PC-DOS Operating Systems

2017-07-07 02:10:07

Declare Function GetClassName Lib "user32.dll" Alias "GetClassNameA" (ByVal hWnd As Long, ByVal lpClassName As String, ByVal nMaxCount 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: Requires Windows CE 1.0 or later.

Description & Usage

GetClassName retrieves the name of the window class to which a window belongs. The name of the class is placed into the string passed as lpClassName.

Return Value

If an error occured, the function returns 0 (use GetLastError to get the error code). If successful, the function returns the number of characters copied into the string passed as lpClassName.

Visual Basic-Specific Issues

None.

Parameters

hWnd: A handle to the window to get the name of the window class of.
lpClassName: A string which receives the name of the window class. This must first be initialized to a sufficient length to receive the string.
nMaxCount: The size in bytes of the string passed as lpClassName.

Example

' This code is licensed according to the terms and conditions listed here. ' Display the name of the window class to which window Form1 belongs. Dim classname As String ' receives the name of the class Dim slength As Long ' length of the string retrieved ' Make room in the string to receive the information. classname = Space(255) ' much more than enough room ' Get the name of the window class. slength = GetClassName(Form1.hWnd, classname, 255) ' Extract the useful information from the string and display it. classname = Left(classname, slength) ' remove empty space Debug.Print "Form1's window class is: "; classname