我有以下C#代码:staticstringTestWebClient(stringurl){varurlFormatted=string.Format(url,List,UserName,AdminPw);varreturnValue="URL:"+urlFormatted+Environment.NewLine;try{using(varclient=newWebClient()){client.Proxy=null;using(vardata=client.OpenRead(urlFormatted)){if(data!=null){using(varreader=newStrea