C# Definition:

[StructLayout(LayoutKind.Sequential)]
public struct MSGBOXPARAMS
{    
    public uint cbSize;
    public IntPtr hwndOwner;
    public IntPtr hInstance;
    public String lpszText;
    public String lpszCaption;
    public uint dwStyle;
    public IntPtr lpszIcon;
    public IntPtr dwContextHelpId;
    public MsgBoxCallback lpfnMsgBoxCallback;
    public uint dwLanguageId;
}

VB Definition:

TODO

User-Defined Field Types:

// Delegate declaration for a callback that gets called when the help button on the message box is pushed.
public delegate void MsgBoxCallback( [HELPINFO] lpHelpInfo );

Notes:

None.