1. 设置你Form的TransparencyKey=某一个颜色如:Color.Red
2. 把你希望透明的地方放一个Panel,设置其Backcolor为1中的颜色
eg:
Code
public Form1() {
InitializeComponent();
TransparencyKey = TransparencyColor;
}
private void button1_Click(object sender, EventArgs e) {
panel1.BackColor = TransparencyColor;
}
private static readonly Color TransparencyColor = Color.Red;