private void WmNCPaint(ref Message m)
{
if (!IsPopupTextBox)
{
base.WndProc(ref m);
return;
}
// Paint over the edges of the text box.
// Using GetWindowDC instead of GetDCEx as GetDCEx seems to return a null handle and a last error of
// the operation succeeded. We're not going to use the clipping rect anyways - so it's not
// that bigga deal.
HandleRef hdc = new HandleRef(this, UnsafeNativeMethods.GetWindowDC(new HandleRef(this, m.HWnd)));
if (hdc.Handle == IntPtr.Zero)
{
throw new Win32Exception();
}
try {
// Dont set the clipping region based on the WParam - windows seems to hack out the two pixels
// intended for the non-client border.
Color outerBorderColor = (MouseIsOver || Focused) ? ColorTable.TextBoxBorder : this.BackColor;
Color innerBorderColor = this.BackColor;
if (!Enabled)
{
outerBorderColor = SystemColors.ControlDark;
innerBorderColor = SystemColors.Control;
}
using (Graphics g = Graphics.FromHdcInternal(hdc.Handle)) {
Rectangle clientRect = AbsoluteClientRectangle;
// could have set up a clip and fill-rectangled, thought this would be faster.
using (Brush b = new SolidBrush(innerBorderColor)) {
g.FillRectangle(b, 0, 0, this.Width, clientRect.Top); // top border
g.FillRectangle(b, 0, 0, clientRect.Left, this.Height); // left border
g.FillRectangle(b, 0, clientRect.Bottom, this.Width, this.Height - clientRect.Height); // bottom border
g.FillRectangle(b, clientRect.Right, 0, this.Width - clientRect.Right, this.Height); // right border
}
// paint the outside rect.
using (Pen p = new Pen(outerBorderColor)) {
g.DrawRectangle(p, 0, 0, this.Width - 1, this.Height - 1);
}
}
}
finally {
UnsafeNativeMethods.ReleaseDC(new HandleRef(this, this.Handle), hdc);
}
// we've handled WM_NCPAINT.
m.Result = IntPtr.Zero;
}
