思路

选择在input的中直接截取字段进行验证,使用一个自定的属性对用户输入的字符串进行判断

<div class="form">
<form action="">

<div class="input-wrap">
<label for="">姓名</label>
<input data-rule="maxlength:10|minlength:2|nullable:false|numeric:false" type="text"        class="input-control">
<div class="input-error">姓名格式输入有误</div>
</div>

</form>

</div>

所以要是一个验证模块

实现Vaildator模块

/**
 * Vaildator验证
 */
$(function () {
    'use strict';

    window.Validator = function (val, rule) {

        this.is_valid = function (new_val) {
            var key;
            if (new_val !== undefined)
                val = new_val;

            /*若不是必填项,且用户未填写任何内容则直接判定为合法*/
            if (!rule.required && !val)
                return true;

            for (key in rule) {
                /*防止重复检查*/
                if (key === 'required')
                    continue;

                /*防止调用rule中相对应的方法*/
                var r = this['validate_' + key]();
                if (!r)
                    return false;
            }
            return true;
        }

        this.validate_max = function () {
            preMaxMin();
            return val <= rule.max;
        }

        this.validate_min = function () {
            preMaxMin();
            return val >= rule.min;
        }


        this.validate_maxlength = function () {
            preLength();
            return val.length <= rule.maxlength;
        }

        this.validate_minlength = function () {
            preLength();
            return val.length >= rule.minlength;
        }

        this.validate_numeric = function () {
            return $.isNumeric(val);
        }

        this.validate_required = function () {
            //防止空格
            var real = $.trim(val);
            if (!real && real !== 0)
                return false;
            return true;
        }

        this.validate_pattern = function () {
            var reg = new RegExp(rule.pattern);
            return reg.test(val);

        }

        /*用于完成min,max方法的前置工作*/
        function preMaxMin() {
            val = parseFloat(val);
        }

        /*用于完成minleng,maxleng方法的前置工作*/
        function preLength() {
            val = val.toString();
        }
    }

});

实现Input

/**
 * Created by tazbingo on 2017/9/26.
 */

$(function () {
    'use strict';

    window.Input = function (selector) {
        var $ele
            , $error_ele
            , me = this
            , rule =
            {
                required: true
            };

        this.loadValidator = function () {
            var val = this.getVal();
            this.validator = new Validator(val, rule);

        }
        this.getVal = function () {
            return $ele.val();
        }

        function init() {
            findEle();
            get_error_ele();
            parseRule();
            me.loadValidator();
            listen();
        }

        function listen() {
            $ele.on('blur', function () {
                var valid = me.validator.is_valid(me.getVal());
                console.log('blur' + valid);
                if (valid)
                    $error_ele.hide();
                else
                    $error_ele.show();
            });
        }

        function get_error_ele() {
            $error_ele = $(get_error_selector());
        }


        function get_error_selector() {
            return '#' + $ele.attr('name') + '-input-error';
        }


        function findEle() {
            if (selector instanceof jQuery)
                $ele = selector;
            else
                $ele = $(selector);
        }

        function parseRule() {
            var i;
            var ruleString = $ele.data('rule');
            if (!ruleString) return;

            var rule_arr = ruleString.split('|');//['min:18','maxlength:10']
            for (i = 0; i < rule_arr.length; i++) {
                var item_str = rule_arr[i];
                var item_arr = item_str.split(':'); //['min','18']
                rule[item_arr[0]] = JSON.parse(item_arr[1]); //['min:18']
            }
        }

        init();
    }

});