<tr> <td> 
 		 <img border='0' src='/_layouts/images/reportsup.gif' alt='Reports to' /> 
  </td> <td>User1 </td> 
  </tr> 
  
  <tr> <td> 
 		 <img src="/_layouts/images/reportsdown.gif" alt="Manager"> 
  </td> <td>User2 </td> 
  </tr> 
  
  <tr> <td> 
  <table> <tr> <td> 
 		 <span/> 
  </td> </tr> </table> 
  </td> <td>User3 </td> 
  </tr>

            //取出图片路径
            MatchCollection mc;
            Regex r = new Regex(@"<img.*?src=(?:""|')?(.*?\.(?:jpg|gif)).*?");
            mc = r.Matches("这里填写你要找的HTML代码 赋值给一个字符串");
            for(int i = 0;i<mc.count;i++)
            {
                //mc[i]就是图片路径了
            }

------解决方案--------------------

C# code

            Regex xxx=new Regex("src=('|\")(?<text>.*)('|\")( alt)");
            string[,] arr = new string[,] { { "","" }, { "","" } };
            int i = 0;
            int j = 0;
            foreach (Match m in xxx.Matches(str)) //str为HTML文档
            {
                //MessageBox.Show(xxx.Match(str).Groups["text"].Value);
                arr[i, j] = m.Groups["text"].Value;
                arr[i++,j + 1] = "User" + i.ToString();
            }
            string x="";  //以下为检测用
            for(int ix=0;ix<i;ix++)
            {
                x+=arr[ix,0].ToString();
                x+="\r\n";
                x+=arr[ix,1].ToString();
                x+="\r\n";
            }
            MessageBox.Show(x);

------解决方案--------------------

C# code
 
     ///  <summary> 
     /// 返回一组标签中指定属性的值小写格式 
     /// 属性值必须被双引号括起来。 
     ///  </summary> 
     ///  <param name="Tag">一组标签 </param> 
     ///  <param name="TagName">属性名称 </param> 
     ///  <returns>属性的小写值 </returns> 
     private string TagVal(string tag, string tagName) 
     { 
       Regex rt = new Regex(@"(? <Keyword>\w+)\s*=\s*(? <Value>" + "\"" + "[^\"]*\")", RegexOptions.Compiled | RegexOptions.IgnoreCase); 
       foreach (Match mt in rt.Matches(tag)) { 
         if (mt.Groups["Keyword"].ToString().Trim().ToLower() == tagName.ToLower()) { 
           return mt.Groups["Value"].ToString().ToLower().Replace("\"", ""); 
         } 
       } 
       return null; 
     } 
     ///去掉所以的html标签，如 <a>aabcd </a>  返回的是aabcd 
     private string DropHTML(string strHtml) 
     { 
       return Regex.Replace(strHtml, " <[^>]*>", ""); 
     }