Transparent WinForms Label

Easy control transparency isn’t exactly a hallmark of Windows Forms. If you have a form with a background image or a gradient, the stock controls paint with a solid background to give a criminally egregious aesthetic.

If you search the web for a solution, you might come up with a couple of proposed solutions:

After working with the second solution for a while, I discovered that it doesn’t handle updating the text very well. Just changing the Text property itself doesn’t do it, and if you invalidate the control, you get the new text painted over the old text. If you’re the kind of person who fusses about minutiae like legibility and such, this isn’t ideal.

So here’s a solution that has worked reasonably well for me, and that scores high marks in the simplicity category:

/// 
/// A label that is transparent.
/// 
public class TransparentLabel : Label
{
  /// 
  /// Paints the background with the parent's background image.
  /// 
  ///
e
  protected override void OnPaintBackground(PaintEventArgs e)
  {
    Rectangle rect = new Rectangle(Location, Size);
    e.Graphics.DrawImage(Parent.BackgroundImage, 0, 0, rect, GraphicsUnit.Pixel);
  }
}

It basically scoops up the correct part of the parent’s background image and uses it as the background for the control. Yes, it still isn’t transparency, just a much better job of “camouflage” than the default behavior. If you’re painting the parent’s background, with a gradient brush for example, you can paint that into a bitmap instead and set the parent’s BackgroundImage to the bitmap for this solution to still work.

One thought on “Transparent WinForms Label

  1. Somebody pointed out the other day that my control didn’t work too well when the text was changed, it does now handle that properly, so you might want to give it another go! No doubt it’ll break in other scenarios though…

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