ASP.NET(C#)图片加文字、图片水印，神啊，看看吧

//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();
}

//using System;
//using System.Web;
//using System.Drawing;
//using System.Drawing.Drawing2D;
//using System.Drawing.Imaging;
//using System.IO;
//using System.Reflection;

/// <summary>
/// 给图片上水印
/// </summary>
/// <param name="filePath">原图片地址</param>
/// <param name="waterFile">水印图片地址</param>
public void MarkWater(string filePath,string waterFile)
{
//GIF不水印
int i = filePath.LastIndexOf(".");
string ex = filePath.Substring(i,filePath.Length - i);
if(string.Compare(ex,".gif",true) == 0)
{
return;
}

string ModifyImagePath = BasePath + filePath;//修改的图像路径
int lucencyPercent=25;
Image modifyImage=null;
Image drawedImage=null;
Graphics g=null;
try
{
//建立图形对象
modifyImage=Image.FromFile(ModifyImagePath,true);
drawedImage=Image.FromFile(BasePath + waterFile,true);
g=Graphics.FromImage(modifyImage);
//获取要绘制图形坐标
int x=modifyImage.Width-drawedImage.Width;
int y=modifyImage.Height-drawedImage.Height;
//设置颜色矩阵
float[][] matrixItems ={
new float[] {1, 0, 0, 0, 0},
new float[] {0, 1, 0, 0, 0},
new float[] {0, 0, 1, 0, 0},
new float[] {0, 0, 0, (float)lucencyPercent/100f, 0},
new float[] {0, 0, 0, 0, 1}};

ColorMatrix colorMatrix = new ColorMatrix(matrixItems);
ImageAttributes imgAttr=new ImageAttributes();
imgAttr.SetColorMatrix(colorMatrix,ColorMatrixFlag.Default,ColorAdjustType.Bitmap);
//绘制阴影图像
g.DrawImage(drawedImage,new Rectangle(x,y,drawedImage.Width,drawedImage.Height),10,10,drawedImage.Width,drawedImage.Height,GraphicsUnit.Pixel,imgAttr);
//保存文件
string[] allowImageType={".jpg",".gif",".png",".bmp",".tiff",".wmf",".ico"};
FileInfo fi=new FileInfo(ModifyImagePath);
ImageFormat imageType=ImageFormat.Gif;
switch(fi.Extension.ToLower())
{
case ".jpg": imageType=ImageFormat.Jpeg; break;
case ".gif": imageType=ImageFormat.Gif; break;
case ".png": imageType=ImageFormat.Png; break;
case ".bmp": imageType=ImageFormat.Bmp; break;
case ".tif": imageType=ImageFormat.Tiff; break;
case ".wmf": imageType=ImageFormat.Wmf; break;
case ".ico": imageType=ImageFormat.Icon; break;
default: break;
}
MemoryStream ms=new MemoryStream();
modifyImage.Save(ms,imageType);
byte[] imgData=ms.ToArray();
modifyImage.Dispose();
drawedImage.Dispose();
g.Dispose();
FileStream fs=null;
File.Delete(ModifyImagePath);
fs=new FileStream(ModifyImagePath,FileMode.Create,FileAccess.Write);
if(fs!=null)
{
fs.Write(imgData,0,imgData.Length);
fs.Close();
}
}
finally
{
try
{
drawedImage.Dispose();
modifyImage.Dispose();
g.Dispose();
}
catch
{
}
}
}

<summary>
/// 添加图片水印
/// </summary>
/// <param name="path">原图片绝对地址</param>
/// <param name="Ext">文件后缀</param>
public static string addWaterMark(string path,string fileExt)
{
System.Drawing.Image image = System.Drawing.Image.FromFile(path);
Bitmap b = new Bitmap(image.Width, image.Height,System.Drawing.Imaging.PixelFormat.Format24bppRgb);
Graphics g = Graphics.FromImage(b);
g.Clear(Color.White);
g.DrawImage(image, 0, 0, image.Width, image.Height);

Image watermark = new Bitmap(ConfigurationSettings.AppSettings["PersonalPath"] + @"images/logo.jpg");

System.Drawing.Imaging.ImageAttributes imageAttributes = new System.Drawing.Imaging.ImageAttributes();
System.Drawing.Imaging.ColorMap colorMap = new System.Drawing.Imaging.ColorMap();
colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);
colorMap.NewColor = Color.FromArgb(0, 0, 0, 0);
System.Drawing.Imaging.ColorMap[] remapTable = {colorMap};
imageAttributes.SetRemapTable(remapTable, System.Drawing.Imaging.ColorAdjustType.Bitmap);
float[][] colorMatrixElements = {
new float[] {1.0f, 0.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 1.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 1.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 0.0f, 0.3f, 0.0f},
new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f}
};
System.Drawing.Imaging.ColorMatrix colorMatrix = new System.Drawing.Imaging.ColorMatrix(colorMatrixElements);
imageAttributes.SetColorMatrix(colorMatrix, System.Drawing.Imaging.ColorMatrixFlag.Default, System.Drawing.Imaging.ColorAdjustType.Bitmap);
int xpos = 0;
int ypos = 0;

xpos = ((image.Width - watermark.Width) - 10);
ypos = image.Height - watermark.Height - 10;

g.DrawImage(watermark, new Rectangle(xpos, ypos, watermark.Width, watermark.Height), 0, 0, watermark.Width, watermark.Height, GraphicsUnit.Pixel, imageAttributes);

watermark.Dispose();
imageAttributes.Dispose();

//保存加水印过后的图片,删除原始图片
Random ro=new Random((int)DateTime.Now.Ticks);
string temppath = System.DateTime.Now.ToString("yyyy") + "//" + System.DateTime.Now.ToString("MMdd");
string fileName = temppath + "//" + DateTime.Now.ToString("yyyyMMddHHmmss") + ro.Next(10000) + fileExt;
string filepath = Functions.GetUserFactPath(User.GetUserFromSession().Adddate,User.GetUserFromSession().UserId) + "3//";

b.Save(filepath + fileName);
b.Dispose();
image.Dispose();
if(File.Exists(path))
{
File.Delete(path);
}

return fileName;
}

/*
* Class:WaterImage
* Use for add a water Image to the picture both words and image
* 2007.07.23   create the file
*
* http://www.freeatom.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; }
}

}