咏竹莉
where there is a will,there is a way
摘要: var Tools = {}; Tools.removeNullOrUndefined = function (obj) { //typeof 返回的是字符串,有六种可能:"number"、"string"、"boolean"、"object"、"function"、"undefined" if ( 阅读全文
posted @ 2021-06-23 17:17 咏竹莉 阅读(243) 评论(0) 推荐(0)
摘要: 变量提升 js的函数定义有个特点,它会先扫描整个函数体的语句,把所有申明的变量"提升"到函数顶部: function log(){ var x = 'hello,' + y; console.log(x); // hello, undefined var y = 'world' } log(); 虽 阅读全文
posted @ 2021-06-23 15:18 咏竹莉 阅读(70) 评论(0) 推荐(0)