一、利用prototype扩展String方法,去除字符前后空格:
String.prototype.trim = function String$trim() { if (arguments.length !== 0) throw Error.parameterCount(); return this.replace(/^s+|s+$/g, ''); }
测试:
var valueStr = " JAVASCRIPT "; alert(valueStr.trim() + "的长度" + valueStr.trim().length);
不管前后有几个空格长度都为10
正则:/^s+|s+$/g 匹配以空格开始或结尾的字符串,/g表示会返回多个结果。
二、利用prototype扩展Array方法,实现冒泡排序:
<script type="text/javascript" language="javascript"> Array.prototype.MaxToMin = function() { var len = this.length; var arr = new Array(len); for (var i = 0; i < len; i++) { for (var j = i + 1; j < len; j++) { if (this[i] < this[j]) { var temp = this[i]; this[i] = this[j]; this[j] = temp; } } } return this; }
测试:
var ArrayInt = new Array(23, 4, 2, 545, 25, 1, 34, 65, 5, 8, 4, 8, 34, 86, 235, 8, 2345, 8, 3245); document.write(ArrayInt.MaxToMin());
结果:3245,2345,545,235,86,65,34,34,25,23,8,8,8,8,5,4,4,2,1
对字符串数组的测试:
var arrayString = new Array("bb", "aa", "cc", "dd"); document.write(arrayString.MaxToMin());
结果:dd,cc,bb,aa