private IntPtr WndProc(IntPtr hWnd, int msg, IntPtr wParam, IntPtr lParam)
{
switch (msg)
{
case 0x118: // Cursor blink message
return(new IntPtr(0));
case Win32Native.WM_KEYDOWN:
case Win32Native.WM_SYSKEYDOWN:
winformSource.HandleKeyDown(wParam, lParam);
if (richTextBox.TextLength == 0)
{
var virtualKey = (System.Windows.Forms.Keys)wParam.ToInt64();
if (virtualKey == System.Windows.Forms.Keys.Back ||
virtualKey == System.Windows.Forms.Keys.Left ||
virtualKey == System.Windows.Forms.Keys.Right ||
virtualKey == System.Windows.Forms.Keys.Delete ||
virtualKey == System.Windows.Forms.Keys.Home ||
virtualKey == System.Windows.Forms.Keys.End ||
virtualKey == System.Windows.Forms.Keys.Up ||
virtualKey == System.Windows.Forms.Keys.Down)
{
// Swallow some keys when the text box is empty to prevent ding sound
return(new IntPtr(0));
}
}
break;
case Win32Native.WM_KEYUP:
case Win32Native.WM_SYSKEYUP:
winformSource.HandleKeyUp(wParam, lParam);
break;
case Win32Native.WM_IME_COMPOSITION:
OnComposition(hWnd, (int)lParam);
break;
case Win32Native.WM_NCPAINT:
case Win32Native.WM_PAINT:
var paintStruct = new Win32Native.PAINTSTRUCT();
Win32Native.BeginPaint(hWnd, ref paintStruct);
Win32Native.EndPaint(hWnd, ref paintStruct);
// Don't paint the control
return(new IntPtr(0));
}
return(Win32Native.CallWindowProc(oldWndProc, hWnd, msg, wParam, lParam));
}