C# 获取URL参数 NameValueCollection

public static NameValueCollection ParseQueryString(string url)        {            NameValueCollection cPar = new NameValueCollection();            url = url.StartsWith("?") ? url.Substring(1) : url;            string[] pairs = url.Split(new char[] { '&' });            int tmpIndex;            foreach (string pair in pairs)            {                if (string.IsNullOrEmpty(pair))                    continue;                tmpIndex = pair.IndexOf('=');                if (tmpIndex == -1)                    continue;                cPar.Add(pair.Substring(0, tmpIndex), pair.Substring(tmpIndex + 1));            }            return cPar;        }