Dotnet水印之2：图片加水印图片

直接贴

/// <summary>
		/// 图片加水印
		/// </summary>
		/// <param name="fileName">源图片文件</param>
		/// <param name="text">水印文字</param>
		/// <param name="newfile">新图片文件名</param>
		public static string PicWaterMark(string SrcFileName,string text,string NewFile) 
		{      	
			return PicWaterMark(SrcFileName,text,NewFile,20.0f, "宋体", 100f, 100f ) ;
		}	
	
		 
		/// <summary>
		/// 图片加水印
		/// </summary>
		/// <param name="SrcFileName">源图片文件</param>
		/// <param name="text">水印文字</param>
		/// <param name="NewFile">新图片文件名</param>
		/// <param name="fontSize">字体大小</param>
		/// <param name="fontName">字体名称</param>
		/// <param name="top">离顶部距离</param>
		/// <param name="left">离左边距离</param>
		/// <returns>返回失败的错误信息1.返回空错误信息表示成功,2.返回非空,即为相应错误信息</returns>
		public static string PicWaterMark(string SrcFileName,string text,string NewFile,float fontSize,string fontName,float top,float left) 
		{ 
			return PicWaterMark( SrcFileName, text, NewFile, fontSize, fontName, top, left,false);
		}
		/// <summary>
		/// 图片加水印
		/// </summary>
		/// <param name="SrcFileName">源图片文件</param>
		/// <param name="text">水印文字</param>
		/// <param name="NewFile">新图片文件名</param>
		/// <param name="fontSize">字体大小</param>
		/// <param name="fontName">字体名称</param>
		/// <param name="top">离顶部距离</param>
		/// <param name="left">离左边距离</param>
		/// <param name="saveNew">新的图片保存方式,如果用此方式,则图片经过编码处理,显示更加清晰,但是size很大;true为新的方式,false为不经过处理方式，图片比较小</param>
		/// <returns>返回失败的错误信息1.返回空错误信息表示成功,2.返回非空,即为相应错误信息</returns>
		public static string PicWaterMark(string SrcFileName,string text,string NewFile,float fontSize,string fontName,float top,float left,bool saveNew) 
		{ 
			if(!File.Exists(SrcFileName)) 
　			{ 
　　			throw new FileNotFoundException("The file don't exist!"); 
　			} 
			System.Drawing.Image imgSrc=null;
			Bitmap bmpSrc =null;
			Graphics g=null;
			try
			{
				//读取源图片文件创建了一个Image 对象
				imgSrc =   System.Drawing.Image.FromFile(SrcFileName);
				int imgSrcWidth =imgSrc.Width;
				int imgSrcHeight=imgSrc.Height;

				//建立一个Format24bppRgb格式 颜色数据的Bitmap对象
				bmpSrc = new Bitmap(imgSrcWidth,imgSrcHeight,
					PixelFormat.Format24bppRgb);

				//从源文件创建的image中创建一个graphics对象
				g =  Graphics.FromImage(bmpSrc);   
				//设置g的呈现质量
				g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias; 
				//按原始大小绘制imgSrc 到Graphics 对象的（x=0,y=0）位置。 
				g.DrawImage(imgSrc,
					new System.Drawing.Rectangle(0,0,imgSrcWidth,imgSrcHeight),
					0,0,imgSrcWidth,imgSrcHeight,
					GraphicsUnit.Pixel);
				//定义字体
				System.Drawing.Font textFont = new System.Drawing.Font(fontName,fontSize); 

				System.Drawing.Color textColor=System.Drawing.Color.Red;
				//定义画刷
				SolidBrush textBrush = new SolidBrush(textColor);

				StringFormat StrFormat = new StringFormat();   
				StrFormat.Alignment = StringAlignment.Center;   
				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 = top; 
				float rectY = left; 
				float rectWidth = text.Length*(fontSize+8); 
				float rectHeight = fontSize+8; 
				//声明矩形域 
				RectangleF textArea = new RectangleF(rectX,rectY,rectWidth,rectHeight);
			
				Brush emptyBrush = new SolidBrush(System.Drawing.Color.Empty); //白笔刷，画背景用 
			
				g.FillRectangle(emptyBrush,rectX,rectY,rectWidth,rectHeight); 
				g.DrawString(text,textFont,textBrush,textArea, StrFormat);  
				//销毁两个Graphic对象，然后把Image 保存到文件系统。,ImageFormat.Jpeg   
				if (saveNew==true)
					SaveImg(bmpSrc,NewFile);
				else
					bmpSrc.Save(NewFile);
				//bmpSrc.Save(NewFile,ImageFormat.Jpeg );   
				ErrorString="";
			}
			catch(Exception ex)
			{
				ErrorString=ex.Message.Trim();
			}
			finally
			{
				if (bmpSrc!=null)
					bmpSrc.Dispose(); 
				if (imgSrc!=null)
					imgSrc.Dispose(); 
				if (g!=null)
					g.Dispose();　  
			}
			return ErrorString;
		}


#region "----------image"
		public static void SaveImg(Bitmap bitmap,string NewFileName)
		{
			long   level=60;
			ImageCodecInfo   myImageCodecInfo; 
			System.Drawing.Imaging.Encoder   myEncoder; 
			EncoderParameter   myEncoderParameter; 
			EncoderParameters   myEncoderParameters; 
                                       
			myImageCodecInfo   =System.Drawing.Imaging.ImageCodecInfo.GetImageEncoders()[0];//GetEncoderInfo( "image/jpeg "); 
              
			//   Create   an   Encoder   object   based   on   the   GUID 
                                          
			//   for   the   Quality   parameter   category. 
			myEncoder   =   System.Drawing.Imaging.Encoder.Quality; 
                                          
			//   Create   an   EncoderParameters   object. 
			//   An   EncoderParameters   object   has   an   array   of   EncoderParameter 
			//   objects.   In   this   case,   there   is   only   one 
                                          
			//   EncoderParameter   object   in   the   array. 
			myEncoderParameters   =   new   EncoderParameters(1); 
                                          
			//   Save   the   bitmap   as   a   JPEG   file   with   给定的   quality   level 
			myEncoderParameter   =   new   EncoderParameter(myEncoder,   level); 
			myEncoderParameters.Param[0]   =   myEncoderParameter; 
			bitmap.Save(NewFileName,   myImageCodecInfo,   myEncoderParameters); 
		}