[js高手之路] 跟GhostWu一起封装一个字符串工具库-扩展trim,trimLeft,trimRight方法(2)

我们接着上一篇的继续，在上一篇我们完成了工具库的架构，本文扩展字符串去空格的方法, 一共有3个

1，trimLeft: 去除字符串左边的空格

2，trimRight: 去除字符串右边的空格

3，trim: 去除字符串两边的空格

 ; (function (window, undefined) {
     function init(obj, s) {
         if (s !== null && s !== undefined) {
             if (typeof s === 'string') {
                 obj.s = s;
             } else {
                 obj.s = s.toString();
             }
         } else {
             obj.s = s;
         }
     }

     function G(s) {
         init(this, s);
     }

     function GhostWu(s) {
         return new G(s);
     }

     var sProto = String.prototype;
     G.prototype = {
         constructor: G,
         capitalize: function () {
             return new this.constructor(this.s.slice(0, 1).toUpperCase() + this.s.substring(1).toLowerCase());
         },
         trimLeft : function () {
             var s;
             if (sProto.trimLeft === 'undefined')
                 s = this.s.trimLeft();
             else
                 s = this.s.replace(/^\s+/g, '');
             return new this.constructor(s);
         },
         trimRight : function () {
             var s;
             if (sProto.trimRight === 'undefined')
                 s = this.s.trimRight();
             else
                 s = this.s.replace(/\s+$/g, '');
             return new this.constructor(s);
         },
         trim : function () {
             var s;
             if (typeof sProto.trim === 'undefined') {
                 s = this.s.replace(/^\s+|\s+$/g, '');
             } else {
                 s = this.s.trim();
             }
             return new this.constructor(s);
         }
     };

     window.G = GhostWu;
 })(window, undefined);

alert( '(' + G( ' ghostwu ' ).s + ')' );

alert( '(' + G( ' ghostwu ' ).trim().s + ')' );

alert( '(' + G( ' ghostwu ' ).trimLeft().trimRight().s + ')' );