JS 添加千分位,测试可以使用 <script language="javascript" type="text/javascript">function comdify(n){ var re=/\d{1,3}(?=(\d{3})+$)/g; var n1=n.replace(/^(\d+)((\.\d+)?)$/,function(s,s1,s2){return s1.replace(re,"$&,")+s2;}); ret
参考了这篇文章 http://www.jb51.net/article/30719.htm var v='Hello World'; (function(){ console.log(v); })() 输出: Hello World 但是 var v='Hello World'; (function(){ console.log(v); var v = 'hi'; })() 输出: undefined 这里面隐藏了一个陷阱-----JavaScript中的变量提升(Hoisting).在JS中,
The Scope Chain JavaScript is a lexically scoped language: the scope of a variable can be thought of as the set of source code lines for which the variable is defined. JS 是一个词法作用域语言,可以理解为变量的作用域就是变量所定义的源代码源代码范围处. Global variables are defined throughou