net 下用javascript调用webservice的话，要用到webservice behavior。下面以一个例子讲解之，比较简单
1 、首先，要创建一个webservice，比如
<%@ webservice language="c#" class=mymath %>
using system;
using system.web.services;
public class mymath {
[webmethod]
public int add(int a, int b)
{
return a + b;
}
[webmethod]
public int subtract(int a, int b)
{
return a - b;
}
}
然后发布，先得到其wsdl。
2、首先，我们要下载webbehavior.htc这个文件（可以到http://msdn.microsoft.com/downloads/samples/internet/behaviors/library/webservice/default.asp.）
去下载，然后放到你的web当前目录下
然后在要调用webserice的页面中，修改如下
<body>
<div id="addservice" style="behavior:url(webservice.htc)"></div>
</body>
这里我们将div id命名为有意义的名称，并且指定style为 webservice行为。接着，我们要书写javascript来调用webserice了：
首先，我们在javascript中，调用其wsdladdservice.useservice("http://localhost/services/math.asmx?wsdl","mymath");
使用id.useservice(wsdll路径,简单的命名方式）;
我们之前设定的id是addservice，而为了给客户端调用方便，我们这里起了名称，叫mymath。而为了保证能正确调用webserice,必须在body里的onload事件里，马上加载处理webservice调用的javascript,如下
<script language="javascript">
function init()
{
addservice.useservice("http://localhost/services/math.asmx?wsdl","mymath"); }
</script>
<body onload="init()">
<div id="service" style="behavior:url(webservice.htc)">
</div>
</body>
在上面，我们通过webservice行为，首先得到了返回webservice的wsdl,接下来我们要进行调用了，调用的格式如下： icallid = id.friendlyname.callservice([callbackhandler,] "methodname", param1, param2, ...);
这里id是我们在div里设置的id,而fridndbyname是我们刚才为方面而起的命，这里就是mymath了，而callbackhandler是使用回调函数的过程名，如果无设置的话，则默认是使用onresult所调用的方法来进行处理，下文会讲到，而param1,,param2等则是说传入的参数了，如：
<script language="javascript">
// all these variables must be global,
// because they are used in both init() and onresult().
var icallid = 0;
var inta = 5;
var intb = 6;
function init()
{
// establish the friendly name "mymath" for the webserviceurl
service.useservice("/services/math.asmx?wsdl","mymath");
// the following method doesnt specify a callback handler, so onwsresult() is used
icallid = service.mymath.callservice("add", inta, intb);
}
function onwsresult()
{
// if there is an error, and the call came from the call() in init()
if((event.result.error)&&(icallid==event.result.id))
{
// pull the error information from the event.result.errordetail properties
var xfaultcode = event.result.errordetail.code;
var xfaultstring = event.result.errordetail.string;
var xfaultsoap = event.result.errordetail.raw;
// add code to handle specific error codes here
}
// if there was no error, and the call came from the call() in init()
else if((!event.result.error) && (icallid == event.result.id))
{
// show the arithmetic!
alert(inta + + + intb + = + event.result.value);
}
else
{
alert("something else fired the event!");
}
}
</script>
<body onload="init()">
<div id="service" style="behavior:url(webservice.htc)" onresult="onwsresult()">
</div>
</body>
注意，用onresult方式返回的话，要在div部分的onresult中指定处理的方法，这里是用onwsresult()方法，其中根据返回的信息来判断是否出错，出错的话则显示。
如果用回调的话，则如下处理
<script language="javascript">
// all these variables must be global,
// because they are used in both init() and onresult().
var icallid = 0;
var inta = 5;
var intb = 6;
function init()
{
// establish the friendly name "mymath" for the webserviceurl
service.useservice("/services/math.asmx?wsdl","mymath");
// the following uses a callback handler named "mathresults"
icallid = service.mymath.callservice(mathresults, "add", inta, intb);
}
function mathresults(result)
{
// if there is an error, and the call came from the call() in init()
if(result.error)
{
// pull the error information from the event.result.errordetail properties
var xfaultcode = result.errordetail.code;
var xfaultstring = result.errordetail.string;
var xfaultsoap = result.errordetail.raw;
// add code to handle specific error codes here
}
// if there was no error
else
{
// show the arithmetic
alert(inta + + + intb + " = " + result.value);
}
}
</script>
<body onload="init()">
<div id="service" style="behavior:url(webservice.htc)">
</div>
</body>
