@msdn=http://search.microsoft.com/search/results.aspx?qu=$$$ @pinvoke=http://pinvoke.net/$$$.htm Summary: The SendMessage API !!!!C# Signature: [DllImport("user32.dll", CharSet = CharSet.Auto)] public static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, nuint wParam, StringBuilder lParam); [DllImport("user32.dll", CharSet = CharSet.Auto)] public static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, nuint wParam, [MarshalAs(UnmanagedType.LPWStr)] string lParam); [DllImport("user32.dll", CharSet = CharSet.Auto)] public static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, nuint wParam, [MarshalAs(UnmanagedType.LPWStr)] string lParam); [DllImport("user32.dll", CharSet = CharSet.Auto)] public static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, nuint wParam, ref nint lParam); [DllImport("user32.dll", CharSet = CharSet.Auto)] public static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, nuint wParam, nint lParam); !!!!VB Signature: <DllImport("user32.dll", CharSet:=CharSet.Auto)> Public Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As IntPtr, ByVal lParam As StringBuilder) As IntPtr End Function <DllImport("user32.dll", CharSet:=CharSet.Auto)> Public Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As IntPtr, <MarshalAs(UnmanagedType.LPWStr)> ByVal lParam As String) As IntPtr End Function <DllImport("user32.dll", CharSet:=CharSet.Auto)> Public Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As Integer, <MarshalAs(UnmanagedType.LPWStr)> ByVal lParam As String) As IntPtr End Function <DllImport("user32.dll", CharSet:=CharSet.Auto)> Public Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As Integer, ByRef lParam As IntPtr) As IntPtr End Function <DllImport("user32.dll", CharSet:=CharSet.Auto)> Public Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As Integer, ByVal lParam As IntPtr) As IntPtr End Function !!!!Notes: None. !!!!Tips & Tricks: Used when propagating environment variables, for instance, updating the Path, without requiring a reboot: see also http://support.microsoft.com/kb/104011 Please add some! !!!!Sample Code: '''C# Samples''' //Set a note to a CommandLink SendMessage(myCommandLink, BCM_SETNOTE, 0, "My CommandLink Note"); //Retrieve a text using WM_GETTEXT int length = SendMessage(myHwndHandle, WM_GETTEXTLENGTH, 0, 0).ToInt32(); StringBuilder builder = new StringBuilder(length); SendMessage(myHwndHandle, WM_GETTEXT, length, builder); '''VB.NET Samples''' Function GetWindowTitle(hWnd As IntPtr) As String Dim length As Integer = SendMessage(hWnd, WM_GETTEXTLENGTH, 0, 0) Dim title As New String(New Char, length) SendMessage(hWnd, WM_GETTEXT, length+1, title) Return title End Function !!!!Alternative Managed API: Do you know one? Please contribute it! Documentation: SendMessage@msdn on MSDN
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