[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 + ')' );