摘要: function a(x,callback) { setTimeout(() => { typeof(callback) 'function'&&callback(x); }, 2000); } a(789,function (num) { console.log(num) }) 阅读全文
posted @ 2021-08-26 09:54 iHadThreeDreams 阅读(15) 评论(0) 推荐(0)