验证策略模式实现

// 定义策略var strategy = {
    isNotEmpty: function(value, errorMsg){
        if(value === ''){            
        return errorMsg;
        }
    },
    minLength: function(value, length, errorMsg){
        if(value.length < length){            
        return errorMsg;
        }
    },
    mobileFormat: function(value, errorMsg){
        if(!/(^1[3|5|8][0-9]{9}$)/.test(value)){            
        return errorMsg;
        }
    }
}function Validator() {
    this.cache = [];
}
Validator.prototype.add = function(value, rules){
    for(var i = 0, rule; rule = rules[i++];){        
    var self = this;
        (function(rule){
            self.cache.push(function(){
                var strategyRule = rule.strategy.split(':');                
                var strategyName = strategyRule.shift();                // 各位看官注意啦， 如果直接使用[value].concat(strategyRule.push(rule.errorMsg))会出问题
                // 什么问题呢？ 
                // strategyRule.push(rule.errorMsg)这货会返回length， 我TM调试了半天！
                strategyRule.push(rule.errorMsg);                
                var arr = [value].concat(strategyRule);                
                return strategy[strategyName].apply(null,arr);
            })
        })(rule);
    }
}
Validator.prototype.check = function(){
    for(var i = 0, checkFn; checkFn = this.cache[i++];){        
    var msg = checkFn();        
    if(msg){            
    return msg;
        }
    }
}var validator = new Validator();
validator.add('12345', [
    {
        strategy: 'isNotEmpty',
        errorMsg: 'in not empty'
    },
    {
        strategy: 'minLength:10',
        errorMsg: 'length is less than 10'
    }
]);var tip = validator.check(); // tip: length is less than 10