下面的例子演示了如何使用Color结构的Alpha成分，首先从Color结构中创建两个Color实例，一个是c1,它是蓝色的，其alpha值为100,另一个是绿色的alpha值为50.接着绘制三个实心图形
public
partial
class
Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Paint( object sender, PaintEventArgs e)
{
Graphics g = e.Graphics;
g.FillRectangle(Brushes.White, this .ClientRectangle);
Color c1 = Color.FromArgb( 100 , Color.Blue);
Color c2 = Color.FromArgb( 50 , Color.Blue);
g.FillEllipse(Brushes.Red, 20 , 20 , 80 , 80 );
Point[] pa = new Point[] {
new Point( 150 , 40 ),
new Point( 90 , 40 ),
new Point( 90 , 120 )
};
g.FillPolygon( new SolidBrush(c2), pa);
}
}
{
public Form1()
{
InitializeComponent();
}
private void Form1_Paint( object sender, PaintEventArgs e)
{
Graphics g = e.Graphics;
g.FillRectangle(Brushes.White, this .ClientRectangle);
Color c1 = Color.FromArgb( 100 , Color.Blue);
Color c2 = Color.FromArgb( 50 , Color.Blue);
g.FillEllipse(Brushes.Red, 20 , 20 , 80 , 80 );
Point[] pa = new Point[] {
new Point( 150 , 40 ),
new Point( 90 , 40 ),
new Point( 90 , 120 )
};
g.FillPolygon( new SolidBrush(c2), pa);
}
}
