private void WmPaint(ref Message m)
{
if (base.DropDownStyle == ComboBoxStyle.Simple)
{
base.WndProc(ref m);
return;
}
if (base.DropDownStyle == ComboBoxStyle.DropDown)
{
if (!_BPainting)
{
var ps = new NativeMethods.PAINTSTRUCT();
_BPainting = true;
NativeMethods.BeginPaint(m.HWnd, ref ps);
RenderComboBox(ref m);
NativeMethods.EndPaint(m.HWnd, ref ps);
_BPainting = false;
m.Result = NativeMethods.TRUE;
}
else
{
base.WndProc(ref m);
}
}
else
{
base.WndProc(ref m);
RenderComboBox(ref m);
}
}
protected override void WndProc(ref Message m)
{
switch (m.Msg)
{
case NativeMethods.WM_PAINT:
if (!_bPainting)
{
NativeMethods.PAINTSTRUCT ps =
new NativeMethods.PAINTSTRUCT();
_bPainting = true;
NativeMethods.BeginPaint(m.HWnd, ref ps);
DrawUpDownButton();
NativeMethods.EndPaint(m.HWnd, ref ps);
_bPainting = false;
m.Result = NativeMethods.TRUE;
}
else
{
base.WndProc(ref m);
}
break;
default:
base.WndProc(ref m);
break;
}
}