ASP.NET(C#)图片加文字、图片水印

/* 
 * Class:WaterImage 
 * Use for add a water Image to the picture both words and image 
 * 2007.07.23   create the file 
 * 
 * http://www.ComponentCN.com/  欢迎您的来访 
 *  
 * 使用说明： 
 * 　建议先定义一个WaterImage实例 
 * 　然后利用实例的属性，去匹配需要进行操作的参数 
 * 　然后定义一个WaterImageManage实例 
 * 　利用WaterImageManage实例进行DrawImage（），印图片水印 
 * 　DrawWords（）印文字水印 
 *  
-*/  
  
using System;  
using System.Drawing;  
using System.Drawing.Imaging;  
using System.Drawing.Drawing2D;  
using System.IO;  
/// <summary>  
/// 图片位置  
/// </summary>  
public enum ImagePosition  
{  
    LeftTop,        //左上  
    LeftBottom,    //左下  
    RightTop,       //右上  
    RigthBottom,  //右下  
    TopMiddle,     //顶部居中  
    BottomMiddle, //底部居中  
    Center           //中心  
}  
  
/// <summary>  
/// 水印图片的操作管理 Design by Gary Gong From Demetersoft.com  
/// </summary>  
public class WaterImageManage  
{  
    /// <summary>  
    /// 生成一个新的水印图片制作实例  
    /// </summary>  
    public WaterImageManage ()  
    {  
        //  
        // TODO: Add constructor logic here  
        //  
    }  
  
    /// <summary>  
    /// 添加图片水印  
    /// </summary>  
    /// <param name="sourcePicture">源图片文件名</param>  
    /// <param name="waterImage">水印图片文件名</param>  
    /// <param name="alpha">透明度(0.1-1.0数值越小透明度越高)</param>  
    /// <param name="position">位置</param>  
    /// <param name="PicturePath" >图片的路径</param>  
    /// <returns>返回生成于指定文件夹下的水印文件名</returns>  
    public string  DrawImage(string sourcePicture,  
                                      string waterImage,  
                                      float alpha,  
                                      ImagePosition position,  
                                      string PicturePath )  
    {  
        //  
        // 判断参数是否有效  
        //  
        if (sourcePicture == string.Empty || waterImage == string.Empty || alpha == 0.0 || PicturePath == string.Empty)  
        {  
            return sourcePicture;  
        }  
  
        //  
        // 源图片，水印图片全路径  
        //  
        string sourcePictureName = PicturePath + sourcePicture;  
        string waterPictureName = PicturePath + waterImage;  
        string fileSourceExtension = System.IO.Path.GetExtension(sourcePictureName).ToLower();  
        string fileWaterExtension = System.IO.Path.GetExtension(waterPictureName).ToLower();  
        //  
        // 判断文件是否存在,以及类型是否正确  
        //  
        if (System.IO.File.Exists(sourcePictureName) == false ||   
            System.IO.File.Exists(waterPictureName) == false ||(  
            fileSourceExtension != ".gif" &&  
            fileSourceExtension != ".jpg" &&  
            fileSourceExtension != ".png") || (  
            fileWaterExtension != ".gif" &&  
            fileWaterExtension != ".jpg" &&  
            fileWaterExtension != ".png")  
            )  
        {  
            return sourcePicture;  
        }  
  
        //  
        // 目标图片名称及全路径  
        //  
        string targetImage = sourcePictureName.Replace ( System.IO.Path.GetExtension(sourcePictureName),"") + "_1101.jpg";  
  
        //  
        // 将需要加上水印的图片装载到Image对象中  
        //  
        Image imgPhoto = Image.FromFile(sourcePictureName);  
        //  
        // 确定其长宽  
        //  
        int phWidth = imgPhoto.Width;  
        int phHeight = imgPhoto.Height;  
  
        //  
        // 封装 GDI+ 位图，此位图由图形图像及其属性的像素数据组成。  
        //  
        Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb);  
  
        //  
        // 设定分辨率  
        //   
        bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);  
  
        //  
        // 定义一个绘图画面用来装载位图  
        //  
        Graphics grPhoto = Graphics.FromImage(bmPhoto);  
  
        //  
        //同样，由于水印是图片，我们也需要定义一个Image来装载它  
        //  
        Image imgWatermark = new Bitmap(waterPictureName);  
          
        //  
        // 获取水印图片的高度和宽度  
        //  
        int wmWidth = imgWatermark.Width;  
        int wmHeight = imgWatermark.Height;  
  
        //SmoothingMode：指定是否将平滑处理（消除锯齿）应用于直线、曲线和已填充区域的边缘。  
        // 成员名称   说明   
        // AntiAlias      指定消除锯齿的呈现。    
        // Default        指定不消除锯齿。    
        // HighQuality  指定高质量、低速度呈现。    
        // HighSpeed   指定高速度、低质量呈现。    
        // Invalid        指定一个无效模式。    
        // None          指定不消除锯齿。   
        grPhoto.SmoothingMode = SmoothingMode.AntiAlias;  
  
        //  
        // 第一次描绘，将我们的底图描绘在绘图画面上  
        //  
        grPhoto.DrawImage(imgPhoto,                                            
                                    new Rectangle(0, 0, phWidth, phHeight),   
                                    0,       
                                    0,         
                                    phWidth,     
                                    phHeight,        
                                    GraphicsUnit.Pixel);      
  
        //  
        // 与底图一样，我们需要一个位图来装载水印图片。并设定其分辨率  
        //  
        Bitmap bmWatermark = new Bitmap(bmPhoto);  
        bmWatermark.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);  
          
        //  
        // 继续，将水印图片装载到一个绘图画面grWatermark  
        //  
        Graphics grWatermark = Graphics.FromImage(bmWatermark);  
  
        //  
        //ImageAttributes 对象包含有关在呈现时如何操作位图和图元文件颜色的信息。  
        //         
        ImageAttributes imageAttributes = new ImageAttributes();  
  
        //  
        //Colormap: 定义转换颜色的映射  
        //  
        ColorMap colorMap = new ColorMap();  
  
        //  
        //我的水印图被定义成拥有绿色背景色的图片被替换成透明  
        //  
        colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);  
        colorMap.NewColor = Color.FromArgb(0, 0, 0, 0);  
  
        ColorMap[] remapTable = { colorMap };  
  
        imageAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap);  
  
        float[][] colorMatrixElements = {   
           new float[] {1.0f,  0.0f,  0.0f,  0.0f, 0.0f}, // red红色  
           new float[] {0.0f,  1.0f,  0.0f,  0.0f, 0.0f}, //green绿色  
           new float[] {0.0f,  0.0f,  1.0f,  0.0f, 0.0f}, //blue蓝色         
           new float[] {0.0f,  0.0f,  0.0f,  alpha, 0.0f}, //透明度       
           new float[] {0.0f,  0.0f,  0.0f,  0.0f, 1.0f}};//  
  
        //  ColorMatrix:定义包含 RGBA 空间坐标的 5 x 5 矩阵。  
        //  ImageAttributes 类的若干方法通过使用颜色矩阵调整图像颜色。  
        ColorMatrix wmColorMatrix = new ColorMatrix(colorMatrixElements);  
  
  
        imageAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default,  
         ColorAdjustType.Bitmap);  
  
        //  
        //上面设置完颜色，下面开始设置位置  
        //  
        int xPosOfWm;  
        int yPosOfWm;   
  
        switch (position)  
        {  
            case ImagePosition .BottomMiddle :  
                xPosOfWm = (phWidth-wmWidth ) / 2 ;  
                yPosOfWm = phHeight- wmHeight -10;  
                break ;  
            case ImagePosition .Center :  
                xPosOfWm = (phWidth - wmWidth) / 2;  
                yPosOfWm = (phHeight-wmHeight ) / 2;  
                break ;  
            case ImagePosition .LeftBottom :  
                xPosOfWm = 10;  
                yPosOfWm = phHeight - wmHeight - 10;  
                break ;  
            case ImagePosition .LeftTop :  
                xPosOfWm = 10;  
                yPosOfWm = 10;  
                break;  
            case ImagePosition .RightTop :  
                xPosOfWm = phWidth - wmWidth - 10;  
                yPosOfWm = 10;  
                break ;  
            case ImagePosition .RigthBottom :  
                xPosOfWm = phWidth - wmWidth - 10;  
                yPosOfWm = phHeight - wmHeight - 10;  
                break ;  
            case ImagePosition.TopMiddle :  
                xPosOfWm = (phWidth - wmWidth) / 2;  
                yPosOfWm = 10;  
                break ;  
            default:  
                xPosOfWm = 10;  
                yPosOfWm = phHeight - wmHeight - 10;  
                break;  
        }  
  
        //  
        // 第二次绘图，把水印印上去  
        //  
        grWatermark.DrawImage(imgWatermark,  
         new Rectangle(xPosOfWm,  
                             yPosOfWm,  
                             wmWidth,  
                             wmHeight),   
                             0,                
                             0,            
                             wmWidth,    
                             wmHeight,     
                             GraphicsUnit.Pixel,    
                             imageAttributes);   
  
         
        imgPhoto = bmWatermark;  
        grPhoto.Dispose();  
        grWatermark.Dispose();  
  
        //  
        // 保存文件到服务器的文件夹里面  
        //  
        imgPhoto.Save(targetImage, ImageFormat.Jpeg);  
        imgPhoto.Dispose();  
        imgWatermark.Dispose();  
        return targetImage.Replace (PicturePath,"");  
    }  
  
    /// <summary>  
    /// 在图片上添加水印文字  
    /// </summary>  
    /// <param name="sourcePicture">源图片文件</param>  
    /// <param name="waterWords">需要添加到图片上的文字</param>  
    /// <param name="alpha">透明度</param>  
    /// <param name="position">位置</param>  
    /// <param name="PicturePath">文件路径</param>  
    /// <returns></returns>  
    public string DrawWords(string sourcePicture,  
                                      string waterWords,  
                                      float alpha,  
                                      ImagePosition position,  
                                      string PicturePath)  
    {  
        //  
        // 判断参数是否有效  
        //  
        if (sourcePicture == string.Empty || waterWords == string.Empty || alpha == 0.0 || PicturePath == string.Empty)  
        {  
            return sourcePicture;  
        }  
  
        //  
        // 源图片全路径  
        //  
        string sourcePictureName = PicturePath + sourcePicture;  
        string fileExtension = System.IO.Path.GetExtension(sourcePictureName).ToLower();  
  
        //  
        // 判断文件是否存在,以及文件名是否正确  
        //  
        if (System.IO.File.Exists(sourcePictureName) == false || (  
            fileExtension != ".gif"  &&  
            fileExtension != ".jpg" &&  
            fileExtension != ".png" ))  
        {  
            return sourcePicture;  
        }  
  
        //  
        // 目标图片名称及全路径  
        //  
        string targetImage = sourcePictureName.Replace(System.IO.Path.GetExtension(sourcePictureName), "") + "_0703.jpg";  
  
        //创建一个图片对象用来装载要被添加水印的图片  
        Image imgPhoto = Image.FromFile(sourcePictureName);  
  
        //获取图片的宽和高  
        int phWidth = imgPhoto.Width;  
        int phHeight = imgPhoto.Height;  
  
        //  
        //建立一个bitmap，和我们需要加水印的图片一样大小  
        Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb);  
  
        //SetResolution：设置此 Bitmap 的分辨率  
        //这里直接将我们需要添加水印的图片的分辨率赋给了bitmap  
        bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);  
  
        //Graphics：封装一个 GDI+ 绘图图面。  
        Graphics grPhoto = Graphics.FromImage(bmPhoto);  
  
        //设置图形的品质  
        grPhoto.SmoothingMode = SmoothingMode.AntiAlias;  
  
        //将我们要添加水印的图片按照原始大小描绘（复制）到图形中  
        grPhoto.DrawImage(  
         imgPhoto,                                           //   要添加水印的图片  
         new Rectangle(0, 0, phWidth, phHeight), //  根据要添加的水印图片的宽和高  
         0,                                                     //  X方向从0点开始描绘  
         0,                                                     // Y方向   
         phWidth,                                            //  X方向描绘长度  
         phHeight,                                           //  Y方向描绘长度  
         GraphicsUnit.Pixel);                              // 描绘的单位，这里用的是像素  
  
        //根据图片的大小我们来确定添加上去的文字的大小  
        //在这里我们定义一个数组来确定  
        int[] sizes = new int[] { 16, 14, 12, 10, 8, 6, 4 };  
  
        //字体  
        Font crFont = null;  
        //矩形的宽度和高度，SizeF有三个属性，分别为Height高，width宽，IsEmpty是否为空  
        SizeF crSize = new SizeF();  
  
        //利用一个循环语句来选择我们要添加文字的型号  
        //直到它的长度比图片的宽度小  
        for (int i = 0; i < 7; i++)  
        {  
            crFont = new Font("arial", sizes[i], FontStyle.Bold);  
  
            //测量用指定的 Font 对象绘制并用指定的 StringFormat 对象格式化的指定字符串。  
            crSize = grPhoto.MeasureString(waterWords, crFont);  
  
            // ushort 关键字表示一种整数数据类型  
            if ((ushort)crSize.Width < (ushort)phWidth)  
                break;  
        }  
  
        //截边5%的距离，定义文字显示(由于不同的图片显示的高和宽不同，所以按百分比截取)  
        int yPixlesFromBottom = (int)(phHeight * .05);  
  
        //定义在图片上文字的位置  
        float wmHeight =  crSize.Height;  
        float wmWidth = crSize .Width ;  
  
        float  xPosOfWm;  
        float  yPosOfWm;   
  
        switch (position)  
        {  
            case ImagePosition .BottomMiddle :  
                xPosOfWm = phWidth / 2 ;  
                yPosOfWm = phHeight- wmHeight -10;  
                break ;  
            case ImagePosition .Center :  
                xPosOfWm = phWidth / 2;  
                yPosOfWm = phHeight / 2;  
                break ;  
            case ImagePosition .LeftBottom :  
                xPosOfWm = wmWidth;  
                yPosOfWm = phHeight - wmHeight - 10;  
                break ;  
            case ImagePosition .LeftTop :  
                xPosOfWm = wmWidth/2 ;  
                yPosOfWm = wmHeight / 2;  
                break;  
            case ImagePosition .RightTop :  
                xPosOfWm = phWidth - wmWidth - 10;  
                yPosOfWm = wmHeight;  
                break ;  
            case ImagePosition .RigthBottom :  
                xPosOfWm = phWidth - wmWidth - 10;  
                yPosOfWm = phHeight - wmHeight - 10;  
                break ;  
            case ImagePosition.TopMiddle :  
                xPosOfWm = phWidth / 2;  
                yPosOfWm = wmWidth;  
                break ;  
            default:  
                xPosOfWm = wmWidth;  
                yPosOfWm = phHeight - wmHeight - 10;  
                break;  
        }  
  
        //封装文本布局信息（如对齐、文字方向和 Tab 停靠位），显示操作（如省略号插入和国家标准 (National) 数字替换）和 OpenType 功能。  
        StringFormat StrFormat = new StringFormat();  
  
        //定义需要印的文字居中对齐  
        StrFormat.Alignment = StringAlignment.Center;  
  
        //SolidBrush:定义单色画笔。画笔用于填充图形形状，如矩形、椭圆、扇形、多边形和封闭路径。  
        //这个画笔为描绘阴影的画笔，呈灰色  
        int m_alpha = Convert .ToInt32 ( 256 * alpha);  
        SolidBrush semiTransBrush2 = new SolidBrush(Color.FromArgb(m_alpha, 0, 0, 0));  
  
        //描绘文字信息，这个图层向右和向下偏移一个像素，表示阴影效果  
        //DrawString 在指定矩形并且用指定的 Brush 和 Font 对象绘制指定的文本字符串。  
        grPhoto.DrawString(waterWords,                                    //string of text  
                                   crFont,                                         //font  
                                   semiTransBrush2,                            //Brush  
                                   new PointF(xPosOfWm + 1, yPosOfWm + 1),  //Position  
                                   StrFormat);  
  
        //从四个 ARGB 分量（alpha、红色、绿色和蓝色）值创建 Color 结构，这里设置透明度为153  
        //这个画笔为描绘正式文字的笔刷，呈白色  
        SolidBrush semiTransBrush = new SolidBrush(Color.FromArgb(153, 255, 255, 255));  
  
        //第二次绘制这个图形，建立在第一次描绘的基础上  
        grPhoto.DrawString(waterWords,                 //string of text  
                                   crFont,                                   //font  
                                   semiTransBrush,                           //Brush  
                                   new PointF(xPosOfWm, yPosOfWm),  //Position  
                                   StrFormat);  
  
        //imgPhoto是我们建立的用来装载最终图形的Image对象  
        //bmPhoto是我们用来制作图形的容器，为Bitmap对象  
        imgPhoto = bmPhoto;  
        //释放资源，将定义的Graphics实例grPhoto释放，grPhoto功德圆满  
        grPhoto.Dispose();  
  
        //将grPhoto保存  
        imgPhoto.Save(targetImage, ImageFormat.Jpeg);  
        imgPhoto.Dispose();  
  
        return targetImage.Replace(PicturePath, "");  
    }  
}  
  
/// <summary>  
/// 装载水印图片的相关信息  
/// </summary>  
public class WaterImage  
{  
    public WaterImage ()  
    {  
  
    }  
  
    private string m_sourcePicture;  
    /// <summary>  
    /// 源图片地址名字(带后缀)  
    /// </summary>  
    public string SourcePicture  
    {  
        get { return m_sourcePicture; }  
        set { m_sourcePicture = value; }  
    }  
  
    private string  m_waterImager;  
    /// <summary>  
    /// 水印图片名字(带后缀)  
    /// </summary>  
    public string  WaterPicture  
    {  
        get { return m_waterImager; }  
        set { m_waterImager = value; }  
    }  
  
    private float  m_alpha;  
    /// <summary>  
    /// 水印图片文字的透明度  
    /// </summary>  
    public float  Alpha  
    {  
        get { return m_alpha; }  
        set { m_alpha = value; }  
    }  
  
    private ImagePosition  m_postition;  
    /// <summary>  
    /// 水印图片或文字在图片中的位置  
    /// </summary>  
    public ImagePosition  Position  
    {  
        get { return m_postition; }  
        set { m_postition = value; }  
    }  
  
    private string  m_words;  
    /// <summary>  
    /// 水印文字的内容  
    /// </summary>  
    public string  Words  
    {  
        get { return m_words; }  
        set { m_words = value; }  
    }  
       
}