提取html中的src 路径

 1  /// <summary>
 2         /// 替换body中的img src属性 附加上域名
 3         /// </summary>
 4         /// <param name="str"></param>
 5         /// <returns></returns>
 6         protected virtual string ReplaceImg(string str)
 7         {
 8             // 定义正则表达式用来匹配 img 标签   
 9             Regex regImg = new Regex(@"<img[^<>]*?src[s	
]*=[s	
]*[""']?[s	
]*(?<imgUrl>[^s	
""'<>]*)[^<>]*?/?[s	
]*>", RegexOptions.IgnoreCase);
10 
11             // 搜索匹配的字符串   
12             MatchCollection matches = regImg.Matches(str);
13             int i = 0;
14             string[] sUrlList = new string[matches.Count];
15 
16             // 取得匹配项列表   
17             foreach (Match match in matches)
18                 sUrlList[i++] = match.Groups["imgUrl"].Value;
19             //return sUrlList;
20             foreach (var item in sUrlList)
21             {
22                 string newStr = _storeContext.CurrentStore.Url + item.Substring(item.IndexOf('/')+1);
23                 str = str.Replace(item, newStr);
24             }
25             return str;
26         }