asp.net ajax 客户端 调用服务器端代码

<asp:ScriptManager  runat="server" />
<div>
    <input type="button" value="Get Server Time"  onclick="return btnGetServerTime_onclick()" />
    <span  />
</div>

然后是客户端JavaScript部分,注意用PageMethods.GetServerTime()这样的形式调用服务器端方法:

function btnGetServerTime_onclick() {
    PageMethods.GetServerTime(cb_getServerTime);
}
function cb_getServerTime(result) {
    document.getElementById("result").innerHTML = result;
}

服务器端代码如下,注意方法必须为静态,且添加[System.Web.Services.WebMethod]和[Microsoft.Web.Script.Services.ScriptMethod]两个属性:

[System.Web.Services.WebMethod]
[Microsoft.Web.Script.Services.ScriptMethod]
public static string GetServerTime()
{
    return DateTime.Now.ToString();
}