javascript调用WCF带参数接口的问题

Question

如题,使用xmlhttprequest向WCF接口发送请求,不带参数的接口可以正常反回,而访问带参数的老是出错,大家看下问题出在哪?WCF服务代码:using System;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.ServiceModel.Activation;
using System.ServiceModel.Web;[ServiceContract(Namespace = "")]
[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class AjaxService
{
// Add [WebGet] attribute to use HTTP GET
[OperationContract]
    [WebGet()]
    public string SayHello()
    {
        // Add your operation implementation here
        return "Hello Ajax Client";
    }    [OperationContract]
    [WebInvoke(ResponseFormat = WebMessageFormat.Json, BodyStyle = WebMessageBodyStyle.Wrapped)]//使用POST方法
    public string SayBye(string name )
    {
        // Add your operation implementation here
        return string.Format("Bye Ajax Client{0}",name);
    }
// Add more operations here and  them with [OperationContract]
}
前台JS代码:function ajaxCall(method)
 {
     var xmlHttp;
     try{// Firefox, Opera 8.0+, Safari
         xmlHttp = new XMLHttpRequest(); //实例化XMLHttpRequest对象
        }
     catch (e)
        {
      // Internet Explorer 5+
       try{
           xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
          }
       catch (e)
          {
          try
             {
                 xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
             }
          catch (e)
             {
                 alert("浏览器不支持AJAX！");
                 return false;
             }
          }
        }
        //绑定数据处理函数。
        xmlHttp.onreadystatechange = function () {
            if (xmlHttp.readyState == 4) {
                if (xmlHttp.status == 200) {
                
               // alert(xmlHttp.responseText);
                 document.getElementById('txtResult').value = xmlHttp.responseText;
                }
                else {
                    alert('请求出错.');
                    // there was a problem with the request,
                    // for example the response may be a 404 (Not Found)
                    // or 500 (Internal Server Error) response codes
                }
            }
        }
        var url = "AjaxService.svc/SayHello";
        if(method=="GET")
        {
            xmlHttp.open("GET",url, true); //异步请求数据
            xmlHttp.send(null);
        }else
        {
            url = "AjaxService.svc/SayBye"
                // Build the body of the JSON message
            var body = '{"name":"sweden"}';
      
        
            // Send the HTTP request
            xmlHttp.open("POST", url, true);
            xmlHttp.setRequestHeader("Content-type", "application/json");
            xmlHttp.send(body);
        }
 }

Answer 1

 var body = '{"name":"sweden"}';
=>
 var body = {"name":"sweden"};

Answer 2

不可以啊,是不是这里要改啊xmlHttp.setRequestHeader("Content-type", "application/json");

Answer 3

<form style="text-align:left">
姓名: <input type="text" id="txtUsername"  style="width:400px;" />
<br />
测试:<input type="button" id="btn"   value="测试GET" onclick=" return ajaxCall('POST');" style="width:400px;" />
<br />
结果: <textarea    id="txtResult" style="width:400px; height:200px"></textarea></form>

Answer 4

xmlHttp.open            
xmlHttp.onreadystatechange=xmlHttpChange;   
xmlHttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded"); 
xmlHttp.send(para);     这个顺序

Answer 5

你看下SayBye(string name ) 执行了么可以借助httpwatch 看下请求的信息

Answer 6

问题解决了,其实是send(body)里的格式问题.
并且实现javascript跨域访问WCF:参考