js策略模式：

var validator = {
    types: {
        isNonEmpty: {
            validate: function (value) {
                return value !== '';
            },
            instructions: '不能为空'
        },
        isNumber: {
            validate: function (value) {
                return !isNaN(value);
            },
            instructions: '只能为数字'
        },
        isAlphaNum: {
            validate: function (value) {
                return !/[^a-z0-9]/i.test(value);
            },
            instructions: '只能为数字与字母的集合，不能包含特殊字符'
        }
    },
    messages:[],
    validate:function(data){
        var i,msg,type,checker,result_ok;
        this.messages = [];
        for(i in data){
            if(data.hasOwnProperty(i)){
                type = this.config[i];
                checker = this.types[type];
                if(!type){
                    continue; //不需要验证，比如last_name,然后进行下一次的循环
                }
                if(!checker){
                    throw  {
                        name:'ValideationError',
                        message : '缺少验证方法:' + type
                    }
                }
                result_ok = checker.validate(data[i]);
                if(!result_ok){
                    msg = '数据'+i+'验证不通过，原因为：'+checker.instructions;
                    this.messages.push(msg);
                }
            }
        }
        return this.hasErrors();
    },
    hasErrors:function(){
        return this.messages.length !== 0;
    }
};

var data = {
    first_name: 'Super',
    last_name: "Man",
    age: "unknown",
    username: "o_O"
};
validator.config = {
    first_name: 'isNonEmpty',
    age: 'isNumber',
    username: 'isAlphaNum'
};
validator.validate(data);