在url中去除指定参数的c#代码

 1        private string buildurl(string url,string param)
 2        {
 3            string url1=url;
 4            if(url.IndexOf(param)>0)
 5            {
 6                if(url.IndexOf("&",url.IndexOf(param)+param.Length)>0)
 7                {
 8                    url1=url.Substring(0,url.IndexOf(param)-1)+url.Substring(url.IndexOf("&",url.IndexOf(param)+param.Length)+1);
 9                }
10                else
11                {
12                    url1=url.Substring(0,url.IndexOf(param)-1);
13                }
14                return url1;
15            }
16            else
17            {
18                return url1;
19            }
20        }

要去除多个参数，这么使用就可以了。buildurl(buildurl(buildurl(url,param1),param2),param3)