如何让webservice输出json格式
[System.Web.Script.Services.ScriptService]public class openapi : System.Web.Services.WebService{ [WebMethod(true)] [ScriptMethod(ResponseFormat = ResponseFormat.Json, UseHttpGet = false,XmlSerializeString=false)] public string login(string s) { return s; }<?xml version="1.0" encoding="utf-8" ?> <string xmlns="http://tempuri.org/">