MVC Razor视图中的AJAX调用

Question

I just noticed a strange behaviour which I am not quite sure about . I am pretty new to jQuery and AJAX. So might just well be missing some basics.

In my MVC rzaor view there are some AJAX Action links which when clicked render a partial view containing the Student Details in the div #StudentDetails.

    <div id="mainpage">

    <h2>Registration Details</h2>
    <ul>
    @foreach(var item in Model) 
    {
        <li>
            @Ajax.ActionLink(item.Student.UserName, @*Text to be displayed *@
            "GetUserDetails", @*Action Method Name*@
            new { id = item.Student.StudentId },
                new AjaxOptions
                {
                    UpdateTargetId = "StudentDetails", @*DOM element ID to be updated *@
                    InsertionMode = InsertionMode.Replace,@*Replace the content of DOM element *@
                    HttpMethod = "GET" @*HTTP method *@,
                    OnComplete="RegisterClickHanders"
                }
            )
        </li>
    }
    </ul>
    <div id ="StudentDetails"></div>
    <br />
    <div id ="Add_Update_Details"></div>
</div>

After the view gets rendered with the details, Edit or Add buttons can be clicked and the appropriate partial views get rendered.

<script>
//Event Delegation
//$(function () {
//One can also use Event Delegation as stated above to handle dynamically added elements i.e. the elements
//that are added after the page is first loaded.
function RegisterClickHanders() {

    var url = '@Url.Action("DisplayClickedView","Private")'; // Name of the action method you want to call and the name of the 
    //controller the action method resides
            $('.editDetails').click(function () {
                var btnvalue = $('.editDetails').attr("value");
                var studentId = $('.editDetails').data("student-id");

                        $('#Add_Update_Details').load(url, { searchText: btnvalue, searchValue: studentId });
            });

            $('.addDetails').click(function () {
                var btnvalue = $('.addDetails').attr("value");

                $('#Add_Update_Details').load(url, { searchText: btnvalue });
            });

}
</script>

In my controller when I put my breakpoints :

they get hit exactly once which is intended. But when I replace the ajax calls as :

        $('.editDetails').click(function () {
        var btnvalue = $('.editDetails').attr("value");
        var studentId = $('.editDetails').data("student-id");

        $.ajax({
            type: 'POST',
            url: url,
            data: { searchText: btnvalue, searchValue: studentId },
            success: function () {
                $('#Add_Update_Details').load(url, { searchText: btnvalue, searchValue: studentId });
            },
            error: function (jqXHR, status, err) {//status is Error and the errorThrown is undefined
                alert('Request Status : ' + jqXHR.status + ' has issued a status text of  : ' + jqXHR.statusText);
            }
        });
    });



    $('.addDetails').click(function () {
        var btnvalue = $('.addDetails').attr("value");

        $.ajax({
            type: 'POST',
            url: url,
            data: { searchText: btnvalue },
            success: function () {
                $('#Add_Update_Details').load(url, { searchText: btnvalue });
            },
            error: function (jqXHR, status, err) {//status is Error and the errorThrown is undefined
                alert('Request Status : ' + jqXHR.status + ' has issued a status text of  : ' + jqXHR.statusText);
            }
        });

    });

The breakpoints in the controller get hit twice upon pressing any of the buttons . What am I missing ? Or is this intended ? Is AJAX call causing a performance hit ?

Answer 1

.load and your ajax call are both calling your controller action.

You should return a PartialView and write it to your empty div like this:

$.ajax({
    type: 'POST',
    url: url,
    data: { searchText: btnvalue, searchValue: studentId },
.success(function (result) {
    $('#Add_Update_Details').html(result);
})