ASP.NET Ajax、PageMethods完整代码

<script>
$.ajax({
    type: "POST",
    url: "UploadPicture.aspx/ModulePhotoUpload",
    data: { argjson: argjson, menuid: menuid },
    contentType: "application/json; charset=utf-8",
    dataType: "json",
    success: function(success) {
        alert(success);
        // Do something interesting here.
    }
});
</script>

body中增加ScriptManager
<asp:ScriptManager ID="ScriptManager1" runat="server" EnablePageMethods="true">
</asp:ScriptManager>

<script>
PageMethods.ModulePhotoUpload(argjson, menuid, InsModulePhotoCallBack);

function InsModulePhotoCallBack(success) {
  alert(success);
}
</script>

后台定义方法可以用：aspx、ashx、asmx、谨记，千万千万别在ascx用户控件后台写。用户控件是无法通过Ajax访问的，会出现“无法访问ascx”错误，PageMethods访问则会报“PageMethods未定义”错误。

/// <summary>
/// 图片上传结果处理
/// </summary>
/// <param name="arg"></param>
/// <returns>1 上传完成，2上传失败</returns>
[System.Web.Services.WebMethod()]
[System.Web.Script.Services.ScriptMethod()]
public static string ModulePhotoUpload(string argjson, int menuid)
{
    //此处实现业务代码
    return "上传完成";
}