are you sure??System.Drawing.Bitmap bmp=new Bitmap(14,14); System.Drawing.Graphics g=Graphics.FromImage(bmp); g.Clear(Color.White); g.DrawString("hello",new Font("Arial",15,FontStyle.Regular,GraphicsUnit.Pixel),new SolidBrush(Color.Black),0,0); for(int i=0;i<14;i++) for(int j=0;j<14;j++) { Color c=bmp.GetPixel(i,j); if (c.B != 0xff) { MessageBox.Show("!"); } }Graphics gh = this.CreateGraphics(); gh.DrawImage(bmp,new Point(10,10));
根本运行以后就看不到hello! 奇怪!
Constants in structure Color (all are public static) RGB value Constants in structure Color (all are public static) RGB value Orange 255, 200, 0 White 255, 255, 255 Pink 255, 175, 175 Gray 128, 128, 128 Cyan 0, 255, 255 DarkGray 64, 64, 64 Magenta 255, 0, 255 Red 255, 0, 0 Yellow 255, 255, 0 Green 0, 255, 0 Black 0, 0, 0 Blue 0, 0, 255
System.Drawing.Graphics g=Graphics.FromImage(bmp);
g.Clear(Color.White);
g.DrawString("hello",new Font("Arial",15,FontStyle.Regular,GraphicsUnit.Pixel),new SolidBrush(Color.Black),0,0);
for(int i=0;i<14;i++)
for(int j=0;j<14;j++)
{
Color c=bmp.GetPixel(i,j);
if (c.B != 0xff)
{
MessageBox.Show("!");
}
}Graphics gh = this.CreateGraphics();
gh.DrawImage(bmp,new Point(10,10));
奇怪!
Color (all are
public static) RGB value
Constants in structure
Color (all are
public static) RGB value
Orange 255, 200, 0 White 255, 255, 255
Pink 255, 175, 175 Gray 128, 128, 128
Cyan 0, 255, 255 DarkGray 64, 64, 64
Magenta 255, 0, 255 Red 255, 0, 0
Yellow 255, 255, 0 Green 0, 255, 0
Black 0, 0, 0 Blue 0, 0, 255
第二行,g使用Graphics的FromImage()建立,再建立一个新的对象后,g(Graphics)就与原来的位图脱离了关系,改变g的内容(譬如调用DrawString()方法)后,为图的内容不会相应变化,此时调用bmp(Bitmap)的GetPixel函数,当然得到的只是原来的bmp图片的内容,里面什么都没有,当然只是0xffff...~~~