摘要: 你肯定见到过这样的代码:a = a||"xxx".它其实就等价于下面三种形式的代码:a = a || "xxx";与:if (!a) { a = "xxx";}和:if (a == null || a == "" || a == undefined) { a = "xxx";}如何理解三种... 阅读全文
posted @ 2014-12-12 10:12 杰克帝.NET 阅读(479) 评论(0) 推荐(0) 编辑