摘要: 1.判断undefined: 1 2 3 4 var tmp = undefined; if (typeof(tmp) == "undefined"){ alert("undefined"); } 1 2 3 4 var tmp = undefined; if (typeof(tmp) == "un 阅读全文
posted @ 2018-01-04 10:23 如果屈原会编程 阅读(126) 评论(0) 推荐(0) 编辑