C# Signature:

[DllImport("user32.dll", SetLastError=true, CharSet=CharSet.Auto)]
static extern uint RegisterWindowMessage(string lpString);

VB Signature:

Declare Function RegisterWindowMessage Lib "user32.dll" (ByVal lpString As String) As Integer

User-Defined Types:

None.

Notes:

None.

Tips & Tricks:

Please add some!

Sample Code:

VB.NET Sample Code

    Dim MessageID As Integer
    MessageID = RegisterWindowMessage("QueryCancelAutoPlay")

C# Sample Code

//Register the message
lMsg = Win32.RegisterWindowMessage("WM_HTML_GETOBJECT");
//Get the object
Win32.SendMessageTimeout(windowHandle, lMsg, IntPtr.Zero, IntPtr.Zero, SendMessageTimeoutFlags.SMTO_ABORT_IF_HUNG, 1000, out lRes);
if(lRes != IntPtr.Zero)
{
    //Get the object from lRes
    htmlDoc= (mshtml.IHTMLDocument)Win32.ObjectFromLresult(lRes, IID_IHTMLDocument, IntPtr.Zero);
    return htmlDoc;
}

C# Sample Code

//provide a private internal message id
private UInt32 queryCancelAutoPlay = 0;

protected override void WndProc(ref Message m)
{
    //calling the base first is important, otherwise the values you set later will be lost
    base.WndProc (ref m);

    //if the QueryCancelAutoPlay message id has not been registered...
    if (queryCancelAutoPlay == 0)
        queryCancelAutoPlay = RegisterWindowMessage("QueryCancelAutoPlay");

    //if the window message id equals the QueryCancelAutoPlay message id
    if ((UInt32)m.Msg == queryCancelAutoPlay)
        m.Result = (IntPtr)1;
} //WndProc

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