另外种Ajax异步调用webservice

在此处我就创建了一个默认的web服务，并不做什么修改，把主要集力放在怎么实现JS调Web服务上面。

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

/// <summary>
///WebService 的摘要说明
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
public class WebService : System.Web.Services.WebService
{

public WebService()
{

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

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

}

第二步：创建一个页面，实现JS调用Web服务

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default3.aspx.cs" Inherits="Default3" %>

<!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>

<script type="text/javascript">
function RequestWebService() {
//这是我们在第一步中创建的Web服务的地址
var URL = "http://localhost/YBWS/WebService.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
var xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
xmlhttp.Open("POST", URL, false);
xmlhttp.SetRequestHeader("Content-Type", "application/soap+xml");
xmlhttp.Send(data);

document.getElementById("data").innerHTML = xmlhttp.responseText;
}
</script>

</head>
<body>
<form id="form1" runat="server">
<div>
<input id="One" type="button" value="JsCallWebService" onclick="RequestWebService()" />
</div>
<div id="data">
</div>
</form>
</body>
</html>