Calling a 'WebMethod' with jQuery in ASP.NET WebForms

问题

I\'ve set a breakpoint in the following WebMethod but I\'m never hitting the breakpoint.

cs:

[WebMethod]
public static string search()
{
    return \"worked\";
}

aspx:

  function search() {
    $.ajax({
        type: \"POST\",
        url: \"ProcessAudit/req_brws.aspx/search\",
        data: \"{}\",
        contentType: \"application/json; charset=utf-8\",
        dataType: \"json\",
        success: function (msg) {
            alert(msg)
        }
    });
}

<button id = \"btnSearch\" onclick = \"search()\" >Search</button>

回答1:

Make sure that you have enabled page methods in your ScriptManager element:

<asp:ScriptManager ID="scm" runat="server" EnablePageMethods="true" />

and that you have canceled the default action of the button by returning false inside the onclick handler, otherwise the page performs a full postback and your AJAX call might never have the time to finish. Here's a full working example:

<%@ Page Language="C#" %>
<script type="text/c#" runat="server">
[System.Web.Services.WebMethod]
public static string search()
{
    return "worked";
}
</script>

<!DOCTYPE html>
<html>
<head id="Head1" runat="server">
    <title></title>
</head>
<body>
    <form id="Form1" runat="server">
        <asp:ScriptManager ID="scm" runat="server" EnablePageMethods="true" />
        <button id="btnSearch" onclick="search(); return false;" >Search</button>
    </form>

    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"></script>
    <script type="text/javascript">
        function search() {
            $.ajax({
                type: 'POST',
                url: '<%= ResolveUrl("~/default.aspx/search") %>',
                data: '{ }',
                contentType: 'application/json; charset=utf-8',
                dataType: 'json',
                success: function (msg) {
                    alert(msg.d)
                }
            });
        }
    </script>
</body>
</html>

Another possibility is to subscribe to the click handler unobtrusively:

<button id="btnSearch">Search</button>

and then inside a separate javascript file:

$('#btnSearch').click(function() {
    $.ajax({
        type: 'POST',
        url: '<%= ResolveUrl("~/default.aspx/search") %>',
        data: '{ }',
        contentType: 'application/json; charset=utf-8',
        dataType: 'json',
        success: function (msg) {
            alert(msg.d)
        }
    });
    return false;
});

You might also notice the usage of the msg.d property inside the success callback which ASP.NET uses to wrap the entire response into as well as the usage of the ResolveUrl method to properly generate the url to the page method instead of hardcoding it.

回答2:

A more optimised call will be

function search() {
    $.ajax({
        type: "POST",
        url: '<%= ResolveUrl("~/ProcessAudit/req_brws.aspx/search") %>',
        data: "{}",
        contentType: "application/json",
        success: function (msg) {
            msg = msg.hasOwnProperty("d") ? msg.d : msg;
            alert(msg);
        }
    });
}

No need to provide a asp:ScriptManager at all.

Resource: http://encosia.com/using-jquery-to-directly-call-aspnet-ajax-page-methods/

回答3:

Your current button is causing a full postback. Simply add a type="button" to your button to avoid this.

 <button id = "btnSearch" type="button" onclick = "search()" >Search</button>

-Shazzam yo

回答4:

How to implement ASP.Net web method using JQuery AJAX ?

HTML Page:

<html xmlns="http://www.w3.org/1999/xhtml">
<head>

    <title></title>
    <script src="js/jquery.min.js"></script>
    <script>
        function SubmitData() {

            var name = 'Ram';
            var gender = 'Male';
            var age = '30';           

            $.ajax({
                type: "POST",
                url: "ajaxcall.aspx/SaveData",
                data: '{"name":"' + name + '", "gender":"' + gender + '", "age":"' + age + '"}',
                contentType: "application/json; charset=utf-8",
                dataType: "json",
                beforeSend: function () {
                    $('#loader').show();
                },
                success: function (data) {

                    alert(data.d);
                    $('#loader').hide();
                },
                error: function (msg) {
                    //alert('3');
                    msg = "There is an error";
                    alert(msg);
                    $('#loader').hide();
                }
            });

        }
    </script>
</head>
<body>
    <div id="loader" style="display: none;">
        <img src="ajax-loader.gif" />
    </div>
    <a href="#" onclick="SubmitData();">Submit</a>
</body>
</html>

Code behind:

[WebMethod]
    public static string SaveData(string name, string gender, string age) {
    try {
        return "OK";
    } catch (Exception ex) {
        return ex.Message;
    } finally { }
}

Resource: http://www.sharepointcafe.net/2016/10/how-to-call-aspnet-web-method-using-jquery-ajax.html

来源：https://stackoverflow.com/questions/6928533/calling-a-webmethod-with-jquery-in-asp-net-webforms

标签

jquery