例子1:
web.config
<httpHandlers> <remove verb="*" path="*.asmx"/> <add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/> <add verb="*" path="*_AppService.axd" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/> <add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" validate="false"/> <add verb="*" path="images/shangjia/*/*.jpg" type="CoverHandler"/> <add verb="*" path="images/shangjia/*/*/*.jpg" type="CoverHandler"/> <add verb="*" path="admin/TotalUpImg/VedioImg/*.jpg" type="CoverHandler1"/> </httpHandlers> <httpHandlers> <remove verb="*" path="*.asmx"/> <add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/> <add verb="*" path="*_AppService.axd" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/> <add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" validate="false"/> <add verb="*" path="images/shangjia/*/*.jpg" type="CoverHandler"/> <add verb="*" path="images/shangjia/*/*/*.jpg" type="CoverHandler"/> <add verb="*" path="admin/TotalUpImg/VedioImg/*.jpg" type="CoverHandler1"/> </httpHandlers>
CoverHandler.cs
using System; using System.Data; using System.Configuration; using System.Web; using System.IO; using System.Drawing; using System.Drawing.Imaging; /// <summary> /// CoverHandler 的摘要说明 /// </summary> public class CoverHandler : IHttpHandler { public CoverHandler() { // // TODO: 在此处添加构造函数逻辑 // } private const string WATERMARK_URL = "~/images/WaterMark.png"; private const string DEFAULTIMAGE_URL = "~/images/default.jpg"; #region IHttpHandler 成员 public void ProcessRequest(HttpContext context) { System.Drawing.Image Cover; if (File.Exists(context.Request.PhysicalPath)) { Cover = Image.FromFile(context.Request.PhysicalPath); Image watermark = Image.FromFile(context.Request.MapPath(WATERMARK_URL)); Graphics g = Graphics.FromImage(Cover); Random r = new Random(); int width = r.Next(10,Cover.Width - watermark.Width); int height = r.Next(10,Cover.Height - watermark.Height); g.DrawImage(watermark, new Rectangle(width, height, watermark.Width, watermark.Height), 0, 0, watermark.Width, watermark.Height, GraphicsUnit.Pixel); g.Dispose(); watermark.Dispose(); } else { Cover = Image.FromFile(context.Request.MapPath(DEFAULTIMAGE_URL)); } context.Response.ContentType = "image/Jpeg"; Cover.Save(context.Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg); Cover.Dispose(); context.Response.End(); } public bool IsReusable { get { return false; } } #endregion }
例子2:
WaterMarke.cs 类 code
using System;using System.Data;using System.Configuration;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;
using System.Drawing;using System.Drawing.Imaging;using System.IO;/// <summary>/// WaterMarker 的摘要说明/// </summary>public class WaterMarker : IHttpHandler{ public WaterMarker() { // // TODO: 在此处添加构造函数逻辑 // } public bool IsReusable { get { return true; } } public void ProcessRequest(HttpContext context) { //获取请求的物理路径 string imagePath = context.Request.PhysicalPath; System.Drawing.Image image = null; //判断指定的物理路径是否存在 if (File.Exists(imagePath)) { //定义水印文字 string text = "本图片来自夏楚枫的博客"; //定义水印文字字体的大小 int fontSize = 12; //水印文字字体 Font font = new Font("宋体", fontSize); //根据图片的物理路径加载图片 image = System.Drawing.Image.FromFile(imagePath); Graphics g = Graphics.FromImage(image); //获取要绘制水印文字所需要区域的大小 SizeF size = g.MeasureString(text, font); if (size.Width > image.Width || size.Height > image.Height) { //如果要显示图片的尺寸都不足以显示按照指定文字字体来添加水印 //可以减小的字体的大小或者不添加水印(太小了没办法添加嘛) } else { //添加水印文字 Brush br = Brushes.Red; g.DrawString(text, font, br, image.Width - size.Width, image.Height - size.Height); g.Dispose(); }} else //如果不存在指定一个默认的图片进行显示 { imagePath = context.Server.MapPath("~/image/default.jpg"); image = System.Drawing.Image.FromFile(imagePath); } image.Save(context.Response.OutputStream, ImageFormat.Jpeg);//将添加水印的图片输出
}}
webconfig 中的配置
方法一:在所在文件夹添加一个webconfig文件,然后再在 <system.web>节点中添加下面的代码
<httpHandlers> <!--对jpg文件添加水印--> <add path="*" verb="*.jpg" type="WaterMarker"/> <!--对bmp文件添加水印--> <add verb="*" path="*.bmp" type="WaterMarker"/> </httpHandlers>
方法二: 不在图片所在的文件夹下添加webconfig 而是直接在根目录下的webconfig中的配置
不用自动生成的那个<System.web>中配置 而是在<configuration>节点中添加如下代码
<location path="image"> <system.web> <httpHandlers> <!--对jpg文件添加水印--> <add path="*" verb="*.jpg" type="WaterMarker"/> <!--对bmp文件添加水印--> <add verb="*" path="*.bmp" type="WaterMarker"/> </httpHandlers> </system.web> </location>