The manner I have used before is to use a wild color (a color no one in their right mind would use) for the BackColor and then set the transparency key to that.
this.BackColor = Color.LimeGreen;
this.TransparencyKey = Color.LimeGreen;
The manner I have used before is to use a wild color (a color no one in their right mind would use) for the BackColor and then set the transparency key to that.
this.BackColor = Color.LimeGreen;
this.TransparencyKey = Color.LimeGreen;