using System;using System.Drawing;using System.Drawing.Drawing2D;using System.Drawing.Imaging;using System.IO;namespace Pub.Class{    ///
/// 添加水印类 只支持添加图片水印    ///
publicclass Watermark    {        #region 私有成员
        privatestring modifyImagePath=null;  privatestring drawedImagePath=null;  privateint rightSpace;  privateint bottoamSpace;  privateint lucencyPercent=70;  privatestring outPath=null;        #endregion#region 构造器
        ///
/// 构造函数        ///
public Watermark() { }        #endregion#region 属性
        ///
/// 获取或设置要修改的图像路径  ///
publicstring ModifyImagePath  {   get{returnthis.modifyImagePath;}   set{this.modifyImagePath=value;}  }  ///
/// 获取或设置在画的图片路径(水印图片)  ///
publicstring DrawedImagePath  {   get{returnthis.drawedImagePath;}   set{this.drawedImagePath=value;}  }  ///
/// 获取或设置水印在修改图片中的右边距  ///
publicint RightSpace  {   get{returnthis.rightSpace;}   set{this.rightSpace=value;}  }  ///
/// 获取或设置水印在修改图片中距底部的高度  ///
publicint BottoamSpace  {   get{returnthis.bottoamSpace;}   set{this.bottoamSpace=value;}  }  ///
/// 获取或设置要绘制水印的透明度,注意是原来图片透明度的百分比  ///
publicint LucencyPercent  {   get{returnthis.lucencyPercent;}   set { if(value>=0&&value<=100) this.lucencyPercent=value; }  }  ///
/// 获取或设置要输出图像的路径  ///
publicstring OutPath  {   get{returnthis.outPath;}   set{this.outPath=value;}        }        #endregion#region 开始绘制水印 DrawImage
        ///
/// 开始绘制水印  ///
/////////     Watermark wm = new Watermark();        ///     wm.DrawedImagePath= Server.MapPath("") + "/upfile/" + "backlogo.gif";        ///     wm.ModifyImagePath=path;         ///     wm.RightSpace=184;        ///     wm.BottoamSpace=81;        ///     wm.LucencyPercent=50;        ///     wm.OutPath=Server.MapPath("") + "/upfile/" + fileName + "_new" + extension;        ///     wm.DrawImage();        //////     //保存加水印过后的图片,删除原始图片         ///     mFileName=fileName + "_new" + extension;        ///     if(File.Exists(path)) {  File.Delete(path); }         //////publicvoid DrawImage()  {   Image modifyImage=null;   Image drawedImage=null;   Graphics g=null;   try {     modifyImage=Image.FromFile(this.ModifyImagePath);//建立图形对象
    drawedImage=Image.FromFile(this.DrawedImagePath);    g=Graphics.FromImage(modifyImage);        int x=modifyImage.Width-this.rightSpace;//获取要绘制图形坐标int y=modifyImage.Height-this.BottoamSpace;        float[][] matrixItems ={//设置颜色矩阵newfloat[] {1, 0, 0, 0, 0},            newfloat[] {0, 1, 0, 0, 0},            newfloat[] {0, 0, 1, 0, 0},            newfloat[] {0, 0, 0, (float)this.LucencyPercent/100f, 0},            newfloat[] {0, 0, 0, 0, 1}};     ColorMatrix colorMatrix = new ColorMatrix(matrixItems);    ImageAttributes imgAttr=new ImageAttributes();    imgAttr.SetColorMatrix(colorMatrix,ColorMatrixFlag.Default,ColorAdjustType.Bitmap);        g.DrawImage(//绘制阴影图像     drawedImage,     new Rectangle(x,y,drawedImage.Width,drawedImage.Height),     0,0,drawedImage.Width,drawedImage.Height,     GraphicsUnit.Pixel,imgAttr);        string[] allowImageType={".jpg",".gif",".png",".bmp",".tiff",".wmf",".ico"};//保存文件
    FileInfo file=new FileInfo(this.ModifyImagePath);    ImageFormat p_w_picpathType=ImageFormat.Gif;    switch(file.Extension.ToLower()) {     case".jpg": p_w_picpathType=ImageFormat.Jpeg; break;     case".gif": p_w_picpathType=ImageFormat.Gif; break;     case".png": p_w_picpathType=ImageFormat.Png; break;     case".bmp": p_w_picpathType=ImageFormat.Bmp; break;     case".tif": p_w_picpathType=ImageFormat.Tiff; break;     case".wmf": p_w_picpathType=ImageFormat.Wmf; break;     case".ico": p_w_picpathType=ImageFormat.Icon; break;     default: break;    }    MemoryStream ms=new MemoryStream();    modifyImage.Save(ms,p_w_picpathType);    byte[] imgData=ms.ToArray();    modifyImage.Dispose();    drawedImage.Dispose();    g.Dispose();    FileStream fs=null;    if(this.OutPath==null || this.OutPath=="") {     File.Delete(this.ModifyImagePath);     fs=new FileStream(this.ModifyImagePath,FileMode.Create,FileAccess.Write);    } else {     fs=new FileStream(this.OutPath,FileMode.Create,FileAccess.Write);    }    if(fs!=null) {     fs.Write(imgData,0,imgData.Length);     fs.Close();    }   } finally {    try {     drawedImage.Dispose();     modifyImage.Dispose();     g.Dispose();    } catch{}   }  }        #endregion    }}

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