{
if (!File.Exists(fileName))
{
throw new FileNotFoundException("文件不存在");
}
if (text == string.Empty)
{
return;
}
//判断文件类型是否为图像类型
System.Drawing.Image image = System.Drawing.Image.FromFile(fileName);
Bitmap bitmap = new Bitmap(image, image.Width, image.Height);
Graphics g = Graphics.FromImage(bitmap);
float fontSize = 12.0f;//字体大小
float textWidth = text.Length * fontSize;//文本的长度
//下面定义一个矩形区域,以后在这个矩形里面画上白底黑字
float rectX = 0;
float rectY = 0;
float rectWidth = text.Length * (fontSize + 8);
float rectHeight = fontSize + 8;
//声明矩形域
RectangleF textArea = new RectangleF(rectX, rectY, rectWidth, rectHeight);
Font font = new Font("宋体", fontSize);//定义字体
Brush whiteBrush = new SolidBrush(Color.White);//白笔刷,画文字用
Brush blackBrush = new SolidBrush(Color.Black);//黑笔刷，画背景用
g.FillRectangle(blackBrush, rectX, rectY, rectWidth, rectHeight);
g.DrawString(text, font, whiteBrush, textArea);
MemoryStream ms = new MemoryStream();
bitmap.Save(ms, ImageFormat.Jpeg);
//输出处理后的图像，这里为了演示方便，我将图片显示在页面中了
//Response.Clear();
//Response.ContentType = "image/jpeg";
//Response.BinaryWrite(ms.ToArray());
g.Dispose();
bitmap.Dispose();
image.Dispose();
}
#endregion
}
}
