同一个文件在前端JS处是否存在的判断方法

有时候需要在js前端来处理同一个文件判断文件是否存在的业务需求。 代码案例如下：

var xmlPath = "{{asset('storage/panos/').'/'.$gid }}/vtour/tour_pro.xml"; $(function () { $.ajax({ headers: {'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')}, url: xmlPath, type: "HEAD", success: function () { //console.log("存在"); embedpano({ swf: "{{asset('storage/panos/').'/'.$gid }}/vtour/tour.swf", id: "krpanoSWFObject", xml: xmlPath, target: "pano", passQueryParameters: true, onready: krpano_onready_callback, }); function krpano_onready_callback(krpano_interface) { krpano = krpano_interface; } }, error: function () { //console.log("不存在"); embedpano({ swf: "{{asset('storage/panos/').'/'.$gid }}/vtour/tour.swf", id: "krpanoSWFObject", xml: "{{asset('storage/panos/').'/'.$gid }}/vtour/tour.xml", target: "pano", passQueryParameters: true, onready: krpano_onready_callback, }); function krpano_onready_callback(krpano_interface) { krpano = krpano_interface; } } }); }) //获取url参数 function getQueryVariable(variable) { var query = window.location.search.substring(1); var vars = query.split("&"); for (var i = 0; i < vars.length; i++) { var pair = vars[i].split("="); if (pair[0] == variable) { return pair[1]; } } return (false); }