string querystring ="sortdir=asc&pag=5";
return RedirectToAction( "Index",ConvertToRouteArray(querystring));

解决方法@H_301_11@

要创建通用解决方案,请将查询字符串转换为Dictionary,并将字典转换为RouteValueDictionary.

var parsed = HttpUtility.ParseQueryString(temp); 
Dictionary<string,object> querystringDic = parsed.AllKeys
    .ToDictionary(k => k,k => (object)parsed[k]); 

return RedirectToAction("Index",new RouteValueDictionary(querystringDic));