<!doctype html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Document</title> <script src="./jquery.js"></script> </head> <body> </body> </html> <script> var getSignal = function(fn){ var ret =''; return function (){ console.log(ret); return ret || (ret = fn.apply(this,arguments)); } } var createDiv=function(){ var div=document.createElement('div') div.innerHTML=' this is login layer '; document.body.appendChild(div); return div; } var createLoginLayer = getSignal(createDiv); var loginLayer2 =createLoginLayer() ; var loginLayer1 = createLoginLayer(); console.log(loginLayer1 == loginLayer2); </script>