异步调用webservice返回responseXML为空的有关问题解决方案

异步调用webservice返回responseXML为空的问题解决方案

先总结几个要领:
1)要熟悉javascript对XML文件的加载与操作;

      感谢q___p的热心回复,原求助帖地址:http://bbs.csdn.net/topics/390399622 ,
      DOM的XML操作可参考的示例:http://www.w3school.com.cn/xmldom/met_document_getelementsbytagname.asp
2)在IE下面还是要通过loadXML来转responseText;
3)xml加载后异步属性设置;
4)命名空间处理等问题;


下面上代码:

========ASPX前台代码========

<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!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></title>            
</head>
<body>
    <form id="form1" runat="server">
    <div id="div1">    
    </div>
    </form>
    <p><input id="Button1" type="button" value="button" onclick="RequestWebService();" /></p>

    <script type="text/javascript">
        var sUsrAgent = navigator.userAgent;
        var isIE = sUsrAgent.indexOf("MSIE") != -1;
        var isIE6 = isIE && sUsrAgent.indexOf("MSIE 6.0") != -1;
        var isIE7 = isIE && sUsrAgent.indexOf("MSIE 7.0") != -1;
        var isFF = sUsrAgent.indexOf("Firefox") != -1;
        var isOP = sUsrAgent.indexOf("Opera") != -1;
        var isSF = sUsrAgent.indexOf("Safari") != -1 && sUsrAgent.indexOf("Chrome") == -1;
        var isCH = sUsrAgent.indexOf("Chrome") != -1; 
        var xmlHttp;        

        function RequestWebService() {
            //这是我们在第一步中创建的Web服务的地址
            var URL = "http://localhost:3165/WebSite2/Service.asmx";

            //在这处我们拼接
            var data;
            data = '<?xml version="1.0" encoding="utf-8"?>';
            data = data + '<soap12:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap12="http://www.w3.org/2003/05/soap-envelope">';
            data = data + '<soap12:Body>';
            data = data + '<HelloWorld xmlns="http://tempuri.org/" />';
            data = data + '</soap12:Body>';
            data = data + '</soap12:Envelope>';

            //创建异步对象
            xmlHttp = GetXmlHttpObject();

            xmlHttp.open("POST", URL, false);

            if (xmlHttp.overrideMimeType) {
                xmlHttp.overrideMimeType('text/xml');
            }            
            xmlHttp.SetRequestHeader("Content-Type", "application/soap+xml");    
            xmlHttp.onreadystatechange = stateChanged;
            xmlHttp.Send(data); 
        }

        function stateChanged() {
            if (xmlHttp.readyState == 4) {
                if (xmlHttp.status == 200) {                
                    alert(xmlHttp.getAllResponseHeaders());
                    alert(xmlHttp.responseText);                                            // 这个有
                    
                    //var xmlDoc = xmlHttp.responseXML;                                     // 这个是空的,但下面会让它出来  
                    
                    var xmlDoc = loadXMLDoc();                               
                    xmlDoc.setProperty("SelectionNamespaces", 'xmlns:soap="http://www.w3.org/2003/05/soap-envelope"    xmlns:ws="http://tempuri.org/" ');
                                                                                            // 这面这段是命名空间(包含显示与匿名的两种)处理方法,必须加上!
                    
                    var node = xmlDoc.selectSingleNode("/soap:Envelope/soap:Body/ws:HelloWorldResponse/ws:HelloWorldResult");  //这边能有值就OK了,为了它前后消耗了1周时间!
                    document.getElementById("div1").innerHTML = node.nodeTypedValue;                                                                
                }
            }
        }

        function GetXmlHttpObject() {
            var xmlHttp = null;
            try {
                // Firefox, Opera 8.0+, Safari
                xmlHttp = new XMLHttpRequest();
            }
            catch (e) {
                // Internet Explorer
                try {
                    xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
                }
                catch (e) {
                    xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
                }
            }
            return xmlHttp;
        }

        function loadXMLDoc() {
            var xmlDoc;

            if (isIE) {
                xmlDoc = getMSXmlParser();
                xmlDoc.async = false;
                xmlDoc.loadXML(xmlHttp.responseText);  //webservice response 需要用loadXML
                //xmlDoc.load(xmlHttp.responseText);   // 加载xml文档需要用load
            }
            else {
                xmlDoc = xmlHttp.responseXML;
                if (!xmlDoc) {
                    xmlDoc = (new DOMParser()).parseFromString(xmlHttp.responseText, 'text/xml');
                }
            }
            return xmlDoc;
        }

        function getMSXmlParser() {
            var parser = [  'Msxml2.DOMDocument.6.0',
                            'Msxml2.DOMDocument.5.0',
                            'Msxml2.DOMDocument.4.0',
                            'Msxml2.DOMDocument.3.0',
                            'MSXML2.DOMDocument',
                            'Microsoft.XMLDOM']; // the same as MSXML.DOMDocument  
            for (var i in parser) {
                try {
                    var xParser = new ActiveXObject(parser[i]);
                    if (xParser) {
                        return xParser;
                    }
                }
                catch (e) { }
            }
            return null;
        }                
    </script>

</body>

</html>



========后台CS文件========

其实这段没有实质内容

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class _Default : System.Web.UI.Page 
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
}


========WebService代码========

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;

[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
// 若要允许使用 ASP.NET AJAX 从脚本中调用此 Web 服务,请取消对下行的注释。
// [System.Web.Script.Services.ScriptService]
public class Service : System.Web.Services.WebService
{
    public Service () {

        //如果使用设计的组件,请取消注释以下行 
        //InitializeComponent(); 
    }

    [WebMethod]
    public string HelloWorld() {
        return "Hello World";
    }
    
}


========返回的responseText========

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<soap:Body>
<HelloWorldResponse xmlns="http://tempuri.org/">
<HelloWorldResult>Hello World</HelloWorldResult>
</HelloWorldResponse>
</soap:Body>
</soap:Envelope>

结束!