data:"{}", data為空白也一定要傳"{}";不然返回的是xml格式的。並提示parsererror
  
  
1、編寫4種WebService方法 
    [WebService(Namespace = "http://tempuri.org/")] 
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)] 
    [ScriptService]                             //令WebService成功傳入Json參數,並以Json形式返回結果 
    [GenerateScriptType(typeof(Person))]        //不是必要,但推薦添加(如果Person裡面再嵌套另一個複雜類型,則必要聲明) 
    [ToolboxItem(false)] 
public class WebService1 : System.Web.Services.WebService 
    { 
/// <summary> 
/// 無任何參數 
/// </summary> 
/// <returns></returns> 
        [WebMethod] 
public string HelloWorld() 
        { 
return "Hello World"; 
        } 
/// <summary> 
/// 傳入參數 
/// </summary> 
/// <param name="name"></param> 
/// <returns></returns> 
        [WebMethod] 
public string Hello(string name) 
        { 
return string.Format("Hello {0}", name); 
        } 
/// <summary> 
/// 返回泛型列表 
/// </summary> 
/// <param name="i"></param> 
/// <returns></returns> 
        [WebMethod] 
public List<int> CreateArray(int i) 
        { 
            List<int> list = new List<int>(); 
while (i >= 0) 
            { 
                list.Add(i--); 
            } 
return list; 
        } 
/// <summary> 
/// 返回複雜類型 
/// </summary> 
/// <param name="name"></param> 
/// <param name="age"></param> 
/// <returns></returns> 
        [WebMethod] 
public Person GetPerson(string name, int age) 
        { 
return new Person() 
            { 
                Name = name, 
                Age = age 
            }; 
        } 
    } 
/// <summary> 
/// 複雜類型 
/// </summary> 
public class Person 
    { 
public string Name { get; set; } 
public int Age { get; set; } 
    } 
2、編寫js調用以上方法 
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="WebApplication1.WebForm1" %> 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head runat="server"> 
<title>無標題頁</title> 
<style type="text/css"> 
    input 
{ 
        width:200px; 
} 
</style> 
<script type="text/javascript" src="jquery-1[1].2.6.min.js"></script> 
<script type="text/javascript"> 
    $(function(){  
/* 
            1、WebService請求類型都為Post,WebService的Url為“[WebServiceUrl]/[WebMethod]” 
            2、contentType聲明為Json 
            3、data要用Json的字串格式傳入 
            4、設定了dataType為json後,result就直接為返回的Json對象。 
*/ 
//調用無參數方法 
        $("#btnHelloWorld").click(function(){ 
            $.ajax({ 
                type: "POST", 
                contentType:"application/json", 
                url:"WebService1.asmx/HelloWorld", 
                data:"{}", 
                dataType:'json', 
                success:function(result){                    
                    alert(result.d); 
                } 
            }); 
        });        
//傳入1個參數 
        $("#btnHello").click(function(){ 
            $.ajax({ 
                type: "POST", 
                contentType:"application/json", 
                url:"WebService1.asmx/Hello", 
                data:"{name:'KiMoGiGi'}", 
                dataType:'json', 
                success:function(result){                    
                    alert(result.d); 
                } 
            }); 
        }); 
//返回泛型列表 
        $("#btnArray").click(function(){ 
            $.ajax({ 
                type: "POST", 
                contentType:"application/json", 
                url:"WebService1.asmx/CreateArray", 
                data:"{i:10}", 
                dataType:'json', 
                success:function(result){                    
                    alert(result.d.join(" | ")); 
                } 
            }); 
        }); 
//返回複雜類型 
        $("#btnPerson").click(function(){ 
            $.ajax({ 
                type: "POST", 
                contentType:"application/json", 
                url:"WebService1.asmx/GetPerson", 
                data:"{name:'KiMoGiGi',age:26}", 
                dataType:'json', 
                success:function(result){ 
var person = result.d; 
var showText = []; 
for(var p in person){ 
                        showText.push(p + ":" + person[p]); 
                    } 
                    alert(showText.join("\r\n")); 
                } 
            }); 
        }); 
    }); 
</script> 
</head> 
<body> 
<form id="form1" runat="server"> 
<p> 
<input type="button" id="btnHelloWorld" value="HelloWorld" /> 
</p> 
<p> 
<input type="button" id="btnHello" value="Hello" /> 
</p> 
<p> 
<input type="button" id="btnArray" value="CreateArray" /> 
</p> 
<p> 
<input type="button" id="btnPerson" value="GetPerson" /> 
</p> 
</form> 
</body> 
</html>