1.修改web.congif
<system.web> <httpHandlers> <remove
verb="*" path="*.asmx"/> <!--解決圖片防盜鏈問題--> <add
verb="*" path="*.jpg" type="MyHttpHandler.Watermark"/> <add
verb="*" path="*.gif" type="MyHttpHandler.Watermark"/> <add
verb="*" path="*.png" type="MyHttpHandler.Watermark"/> </httpHandlers></system.web> |
2.添加一個一般執行文件Watermark.ashx，代碼如下：
using System;using System.Data;using System.Web;using System.Collections;using System.Web.Services;using System.Web.Services.Protocols;using System.Drawing.Imaging;using System.Drawing;using System.IO;namespace MyHttpHandler{ ///
<summary> ///
Summary description for $codebehindclassname$ ///
</summary> [WebServiceBinding(ConformsTo
= WsiProfiles.BasicProfile1_1)] public class Watermark
: IHttpHandler { public bool IsReusable { get { return false; } } public void ProcessRequest(HttpContext
context) { //設置客戶端緩衝時間過期時間爲0，即立即過期 //context.Response.Expires
= 0; //清空服務器端爲此會話開啓的輸出緩存 //context.Response.Clear(); //設置輸出文件類型 context.Response.ContentType
= "image/jpg"; //將請求文件寫入到輸出緩存中 #region
獲取XML配置信息 DataSet
dsConfing = new DataSet(); string watermarkConfigPath
= context.Server.MapPath("~/Config/WaterMarkConfig.xml"); if (System.IO.File.Exists(watermarkConfigPath)) dsConfing.ReadXml(watermarkConfigPath); else { //添加默認的水印配置 } DataRow
drConfing = dsConfing.Tables[0].Rows[0]; #endregion string currentHost
= drConfing["allowhost"].ToString(); //判斷是否是本地網站引用圖片，如果是則返回正確的圖片 if (context.Request.Url.Authority.Equals(currentHost,
StringComparison.InvariantCultureIgnoreCase)) { string localPath
= context.Request.Url.LocalPath; localPath
= localPath.Remove(localPath.LastIndexOf('/')).ToLower();//
"/images/userphoto" if (drConfing["isflag"].Equals("true")
&& drConfing["files"].ToString().ToLower().IndexOf(localPath)
> 0) { #region
水印代碼 string sImgStartPhysicalPath
= context.Request.PhysicalPath; System.Drawing.Image
imgStart = System.Drawing.Image.FromFile(sImgStartPhysicalPath); //備份原圖片 //int
indexOf = sImgStartPhysicalPath.LastIndexOf("."); //string
bakPath = sImgStartPhysicalPath.Remove(indexOf) + "_bak" + sImgStartPhysicalPath.Substring(indexOf); //imgStart.Save(bakPath); Graphics
gh = System.Drawing.Graphics.FromImage(imgStart); if (drConfing["type"].Equals("img")) { System.Drawing.Image
imgWatermark = System.Drawing.Image.FromFile(context.Server.MapPath(drConfing["img-path"].ToString())); Rectangle
rg = SetImgPosition(drConfing["position"].ToString(),
imgStart.Width, imgStart.Height, imgWatermark.Width, imgWatermark.Height); gh.DrawImage(imgWatermark,
rg, 0, 0, imgWatermark.Width, imgWatermark.Height, GraphicsUnit.Pixel); gh.Save(); gh.Dispose(); imgWatermark.Dispose(); } else if (drConfing["type"].Equals("font")) { //文字水印 string content
= drConfing["font-content"].ToString(); float Size
= (float)Convert.ToDouble(drConfing["font-size"].ToString()); FontStyle
fontStyle = (FontStyle)int.Parse(drConfing["font-style"].ToString()); System.Drawing.Font
f = new System.Drawing.Font("Arial",
Size, fontStyle); Color
G_Color = Color.FromName(drConfing["font-color"].ToString()); System.Drawing.Brush
b = new System.Drawing.SolidBrush(G_Color); SizeF
sizeF = gh.MeasureString(content, f); gh.DrawString(content,
f, b, SetFontPosition(drConfing["position"].ToString(),
imgStart.Width, imgStart.Height, (int)sizeF.Width,
(int)sizeF.Height)); gh.Save(); gh.Dispose(); } //將請求文件寫入到輸出緩存中 imgStart.Save(context.Response.OutputStream,
ImageFormat.Jpeg); imgStart.Dispose(); #endregion } else { #region
輸出原圖 //將請求文件寫入到輸出緩存中 context.Response.WriteFile(context.Request.Url.AbsolutePath); #endregion } } //如果不是本地引用，則是盜鏈本站圖片 else { //將請求文件寫入到輸出緩存中 context.Response.WriteFile(context.Request.PhysicalApplicationPath
+ drConfing["errimgpath"].ToString());
} //將輸出緩存中的信息傳送到客戶端 context.Response.End(); } ///
<summary> ///
圖片繪畫水印的位置 ///
</summary> ///
<param name="positionConfig">位置類型</param> ///
<param name="width">原圖片寬</param> ///
<param name="height"></param> ///
<param name="watermarkWidth">水印圖寬</param> ///
<param name="watermarkHeight"></param> ///
<returns></returns> private Rectangle
SetImgPosition(string positionConfig,int width,int height,int watermarkWidth,int watermarkHeight) { int xpos
= 0; int ypos
= 0; int margin
= 10; int width_margin
= width - margin; int height_margin
= height - margin; double proportion
= 1d;//水印圖片縮放比例 //int
if ((width_margin
> watermarkWidth * proportion) && (height_margin > watermarkHeight * proportion)) { } else if ((width_margin
> watermarkWidth * proportion) && (height_margin < watermarkHeight * proportion)) { proportion
= Convert.ToDouble( height_margin) / Convert.ToDouble( watermarkHeight); } else if ((width_margin
< watermarkWidth * proportion) && (height_margin > watermarkHeight * proportion)) { proportion
= Convert.ToDouble(width_margin) / Convert.ToDouble(watermarkWidth); } else { double proportionW
= Convert.ToDouble(width_margin) / Convert.ToDouble(watermarkWidth); double proportionH
= Convert.ToDouble(height_margin) / Convert.ToDouble(watermarkHeight);
proportion
= proportionW >= proportionH ? proportionH : proportionW; } watermarkWidth
= Convert.ToInt32(watermarkWidth * proportion); watermarkHeight
= Convert.ToInt32(watermarkHeight * proportion); switch (positionConfig) { case "top-left": xpos
= margin; ypos
= margin; break; case "top-right": xpos
= width_margin - watermarkWidth; ypos
= margin; break; case "bottom-left": xpos
= margin; ypos
= height_margin - watermarkHeight; break; case "bottom-right": xpos
= width_margin - watermarkWidth ; ypos
= height_margin - watermarkHeight ; break; default: xpos
= width_margin - watermarkWidth ; ypos
= height_margin - watermarkHeight; break; } return new Rectangle(xpos,ypos,watermarkWidth,watermarkHeight); } ///
<summary> ///
圖片繪畫文字位置 ///
</summary> ///
<param name="positionConfig">位置類型</param> ///
<param name="width">原圖片寬</param> ///
<param name="height"></param> ///
<param name="fontWidth">文字長度</param> ///
<param name="fontHeight"></param> ///
<returns></returns> private Point
SetFontPosition(string positionConfig,
int width,
int height,
int fontWidth,
int fontHeight) { int xpos
= 0; int ypos
= 0; int margin
= 10; int width_margin
= width - margin; int height_margin
= height - margin; double proportion
= 1d;//水印圖片縮放比例 //int
if ((width_margin
> fontWidth * proportion) && (height_margin > fontHeight * proportion)) { } else if ((width_margin
> fontWidth * proportion) && (height_margin < fontHeight * proportion)) { proportion
= Convert.ToDouble(height_margin) / Convert.ToDouble(fontHeight); } else if ((width_margin
< fontWidth * proportion) && (height_margin > fontHeight * proportion)) { proportion
= Convert.ToDouble(width_margin) / Convert.ToDouble(fontWidth); } else { double proportionH
= Convert.ToDouble(height_margin) / Convert.ToDouble(fontHeight); double proportionW
= Convert.ToDouble(width_margin) / Convert.ToDouble(fontWidth); proportion
= proportionW >= proportionH ? proportionH : proportionW; } fontWidth
= Convert.ToInt32(fontWidth * proportion); fontHeight
= Convert.ToInt32(fontHeight * proportion); switch (positionConfig) { case "top-left": xpos
= margin; ypos
= margin; break; case "top-right": xpos
= width_margin - fontWidth; ypos
= margin; break; case "bottom-left": xpos
= margin; ypos
= height_margin - fontHeight; break; case "bottom-right": xpos
= width_margin - fontWidth; ypos
= height_margin - fontHeight; break; default: xpos
= width_margin - fontWidth; ypos
= height_margin - fontHeight; break; } return new Point(xpos,
ypos); } }} |
3.配置文件的WaterMarkConfig.xml，內容如下：
<?xml
version="1.0" encoding="utf-8" ?><watermark> <allowhost>localhost:6219</allowhost><!--允許訪問的域名--> <isflag>true</isflag><!--
true、false--> <type>font</type><!--
img、font--> <files>/config|/upfiles/ab</files><!--需要加水印的文件夾--> <position>bottom-right</position><!--
top-left、top-right、bottom-left、bottom-right--> <img-path>~/UpFiles/Watermark.png</img-path><!--
水印位置 --> <font-style>1</font-style><!--普通文本
0, 加粗文本 1, 傾斜文本 2, 帶下劃線的文本 4, 中間有直線通過的文本 8--> <font-size>60</font-size> <font-color>red</font-color> <font-content>￥：8000元</font-content>
<errimgpath>images/error.jpg</errimgpath><!--
盜圖片的請求返回的跟目錄下的某圖片 --></watermark> |