Ajax.ActionLink not working, Response.IsAjaxRequest() is always false

Question

I have been googling/SO:ing this issue for a while and many seem to be sharing this, but I haven\'t found any successful solution to my problem.

Using MVC3 and Razor

Answer 1

By default ASP.NET MVC 3 uses unobtrusive jquery with all the Ajax.* helpers. So start by getting rid off all MicrosoftAjax scripts (this useless c**p) and put the following instead:

<script src="@Url.Content("~/Scripts/jquery-1.5.min.js")" type="text/javascript"></script>
<script src="@Url.Content("~/Scripts/jquery.unobtrusive-ajax.min.js")" type="text/javascript"></script>

and then simply activate unobtrusive AJAX in your web.config (if not already done):

<appSettings>
    <add key="ClientValidationEnabled" value="true"/> 
    <add key="UnobtrusiveJavaScriptEnabled" value="true"/> 
</appSettings>

Now jquery is going to unobtrusively AJAXify all the links containing those HTML 5 data-* attributes.

Or even better IMHO:

In your view simply:

@Html.ActionLink("Update", "AjaxTester", new { id = "mylink" })

and in a separate javascript file AJAXify this anchor:

$(function() {
    $('#mylink').click(function() {
        $('#AjaxTestDiv').load(this.href);
        return false;
    });
});

Answer 2

For those still facing this issue:

You should have below files in your project somewhere:

If not, below is the nuget package, either download this from nuget manager in your visual studio project or package manager console: https://www.nuget.org/packages/Microsoft.jQuery.Unobtrusive.Validation/3.2.11/

Give reference of above added file after the jquery.min.js latest version in either your respective view or layout file:

Answer 3

Another IE-specific issue that can keep ActionLink from functioning correctly is covered here: ASP.NET MVC - Prevent Cache on Ajax.ActionLinks

Basically, IE sometimes caches Ajax GET requests, so setting the AjaxOption's HttpMethod to POST is a less fragile way to construct an ActionLink:

@Ajax.ActionLink(
       item.Name + " (Ajax link test)",
         "MyActionName",
         routeValues: new { id = item.Id },
         ajaxOptions: new AjaxOptions()
         {
              UpdateTargetId = "divToUpdate",
              InsertionMode = InsertionMode.Replace,
              HttpMethod = "POST"
         })