My Js code. 
-------

  $(document).ready(function () {
                $("[id*=ImgBtn_DL]").click(function () {
                    var row = $(this).closest("tr");
                    var fileName = row.find("td:eq(16)").text().trim();
                    var url = "Files/PDFs/" + fileName;
                    $.ajax({
                        url: url,
                        cache: false,
                        xhr: function () {
                            var xhr = new XMLHttpRequest();
                            xhr.onreadystatechange = function () {
                                if (xhr.readyState == 2) {
                                    if (xhr.status == 200) {
                                        xhr.responseType = "blob";
                                    } else {
                                        xhr.responseType = "text";
                                    }
                                }
                            };
                            return xhr;
                        },
                        success: function (data) {
                            var blob = new Blob([data], { type: "application/octetstream" });
                            var isIE = false || !!document.documentMode;
                            if (isIE) {
                                window.navigator.msSaveBlob(blob, fileName);
                            } else {
                                var url = window.URL || window.webkitURL;
                                link = url.createObjectURL(blob);
                                var a = $("<a />");
                                a.attr("download", fileName);
                                a.attr("href", link);
                                $("body").append(a);
                                a[0].click();
                                $("body").remove(a);
                            }
                        }
                    });
                });
            });