file download by calling .ashx page

I'm requesting .ashx page from Master page client side script (Jquery) which has a code to download a PDF file. When I debug it, I can see the execution of "file download" code but file is not downloading.

$.ajax({
    type: "POST",
    url: "FileDownload.ashx",
    dataType: "html",
    success: function (data) { }
} );

public class FileDownload : IHttpHandler
{
    public void ProcessRequest(HttpContext context)
    {
        //context.Response.ContentType = "text/plain";
        //context.Response.Write("Hello World");

        string fileName = "BUSProjectCard.pdf";
        string filePath = context.Server.MapPath("~/Print/");
        context.Response.Clear();
        context.Response.ContentType = "application/pdf";
        context.Response.AddHeader("Content-Disposition", "attachment; filename="+fileName);
        context.Response.TransmitFile(filePath + fileName);
        context.Response.End();
    }