js substring从右边获取指定长度字符串(示例代码)_javascript技巧

如下所示：复制代码 代码如下: /* Get the rightmost substring, of the specified length, from a String object. */ String.prototype.right = function (length_) { var _from = this.length - length_; if (_from return this.substring(this.length - length_, this.length); };