Filter in Select Option List With Textbox (Old Browser)

index.html

<script type="text/javascript">
		$(document).ready(function() {

			$("#searchBoxForOldBrowsers").keyup(function() {
				searchInListForOldBrowsers();
			});
      
		});
		
		var searchInListForOldBrowsers = function() {
			var myOptions = document.getElementById($('#myOptions').get(0).id);
			var searchBox = document.getElementById($('#searchBoxForOldBrowsers').get(0).id);

			$.each(myOptions, function(index, item) {
				$(item).css("visibility", "hidden");
				$(item).attr("disabled", "true");
				var writtenValue = item.innerText.toUpperCase();
				var searchedValue = searchBox.value.toUpperCase();

				if (writtenValue == "" || searchedValue == "" || writtenValue.indexOf(searchedValue) >= 0) {
					$(item).css("visibility", "visible");
					$(item).removeAttr("disabled");
					if (searchedValue != "" && index != 0) {
						$('select[name="' + document.getElementById($('#myOptions').get(0).id).name + '"] option:eq(' + index + ')').insertBefore(
								$('select[name="' + document.getElementById($('#myOptions').get(0).id).name + '"] option:eq(0)'))
					}
				}
			});
		};
</script>