using System.Drawing; using System.IO; using System.Drawing.Imaging; private void AddTextToImg(string fileName,string text) { if(!File.Exists(MapPath(fileName))) { throw new FileNotFoundException("The file don‘t exist!"); } if( text == string.Empty ) { return; } //还需要判断文件类型是否为图像类型,这里就不赘述了 System.Drawing.Image image = System.Drawing.Image.FromFile(MapPath(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( ); //保存为Jpg类型 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(); }
调用时很简单,
AddTextToImg("me.jpg","程序人生http://www.manong123.com/");
一切OK了,感觉.net确实好强大,这些功能在Asp中可是奢侈品了,而在.Net环境中却能轻而易举的完成!
在Asp.net中为图像加入水印信息
时间: 2024-10-06 19:25:18