Controller Void Method On Button Click Using Ajax. ASP.NET

Well there can be several reasons why your code is not working.

1. First Make sure you are actually able to make a call to a function, Just simply add simple alert message before calling the ajax and see if the alert triggers.

2. The second thing is to validate url replace the hardcoded url and add url using URL helper.

3. I would recommend you to make a function as JsonResult Instead of Void, because an exception can happen when creating pdf. [This change is optional but I do recommend it]

So after all the changes your code would look something like this

@{
      ViewBag.Title = "Home Page";
    }


    <div class="row">
      <div class="col-md-12">
        <h2>Request employement certificate</h2>

        <input type="button" onclick="BtnClick()" value="Click me" />

      </div>
    </div>
    <script>
      function BtnClick() {
        $ajax({
          alert("Funciton is working"); // change confirm function is working
          url: "@Url.Action("Test","Home")", // change using Url Helper to create valid URL
          method: "POST",
          success: function (data) {
             if (data == true)
                {
                  alert("pdf created sucessfully ok");
                }
             else
                {
                 alert("exception happend when creating pdf not ok");
                }

          },
          error: function () {
            alert("not ok")
          }
        })
      }

</script>

Your Back End would look something like this

[HttpPost]
public JsonResult Test()

{

    try {
        string dok = System.IO.File.ReadAllText("C:\\Users\\axel\\Desktop\\Repo\\Cert\\employee_regular.html");
        var Renderer = new IronPdf.HtmlToPdf();
        var HtmlTemplate = dok;

        var Pdf = Renderer.RenderHtmlAsPdf(HtmlTemplate);
        Pdf.SaveAs("C:\\Users\\axel\\Desktop\\Repo\\Cert\\Arbetsgivarintyg_vanlig_heltid.pdf");
        return Json(true, JsonRequestBehavior.AllowGet);
    }
    catch(Exception ex) {
        return Json(false, JsonRequestBehavior.AllowGet);
    }

}