Ajax Beforesend Write Show hidden code does not execute

Ajax if you want to write like below format

$.ajax ({url:ajaxurl,type: ' POST ', DataType: ' JSON ', Async:true,data: {},beforesend:function () {
Here the execution of the animation to be performed maskController.methods.show ("Img/loading_icon1.gif", $ ("body")),},success:function (data) {$.each ( Data["Objects"], function (key, value) {if (value["Fields" ["status"] = = "Active") {callback (data);});},error: function (data) {},complete:function () {
Hide animation maskController.methods.hide ();})

　　

Async:false will not perform operations such as display hiding, for specific reasons, in-depth study later. Take notes first, write down

Ajax Beforesend Write Show hidden code does not execute