vue 使用自定义指令实现表单校验的方法

import Vue from 'vue'

const IP_REGEX = '^(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|[1-9])\\.' +
'(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\.' +
'(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\.' +
'(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)$'

// 注册一个全局自定义指令 `v-checkParam`
Vue.directive('checkParam', {
 // 当被绑定的元素插入到 DOM 中时……
 inserted: function (el, binding, vNode) {
  el.addEventListener('keyup', function (event) {
   // 首先去除已有样式
   el.className = el.className.replace('input-error', '').trim()
   // if (!event.keyCode) { // 加上这个判断就是在提交时，才会校验
    // 判断是否是否必填
   let isRequired = binding.value.required
   if (isRequired) {
    if (!el.value || el.value === '') {
     el.className += ' input-error'
    }
   }

    // 判断正则
    // debugger
   let regex = binding.value.regex
   if (regex === 'IpRegex') {
    if (!el.value.match(IP_REGEX)) {
     el.className += ' input-error'
    }
   } else if (!el.value.match(regex)) {
    el.className += ' input-error'
   }
   // }
  })
 }
})

// 注册一个全局自定义指令 `v-checkSubmit`
Vue.directive('checkSubmit', {
 // 当被绑定的元素插入到 DOM 中时……
 inserted: function (el, binding, vNode) {
  el.addEventListener('click', function (event) {
   let elements = document.getElementsByClassName('v-check')
   var evObj = document.createEvent('Event')
   evObj.initEvent('keyup', true, true)
   for (let element of elements) {
    element.dispatchEvent(evObj)
   }
   let errorInputs = document.getElementsByClassName('input-error');
   if(errorInputs.length === 0){
    vNode.context.submit();
   }
  })
 }
})

import Vue from 'vue'

const IP_REGEX = '^(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|[1-9])\\.' +
'(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\.' +
'(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\.' +
'(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)$'

// 注册一个全局自定义指令 `v-checkParam`
Vue.directive('checkParam', {
 // 当被绑定的元素插入到 DOM 中时……
 inserted: function (el, binding, vNode) {
  el.addEventListener('keyup', function (event) {
   // 首先去除已有样式
   el.className = el.className.replace('input-error', '').trim()
   if (!event.keyCode) { // 加上这个判断就是在提交时，才会校验
    // 判断是否是否必填
    let isRequired = binding.value.required
    if (isRequired) {
     if (!el.value || el.value === '') {
      el.className += ' input-error'
     }
    }

    // 判断正则
    let regex = binding.value.regex
    if (regex === 'IpRegex') {
     if (!el.value.match(IP_REGEX)) {
      el.className += ' input-error'
     }
    }
    else if (!el.value.match(regex)) {
     el.className += ' input-error'
    }
   }
  })
 }
})

// 注册一个全局自定义指令 `v-checkSubmit`
Vue.directive('checkSubmit', {
 // 当被绑定的元素插入到 DOM 中时……
 inserted: function (el, binding, vNode) {
  el.addEventListener('click', function (event) {
   let elements = document.getElementsByClassName('v-check')
   var evObj = document.createEvent('Event')
   evObj.initEvent('keyup', true, true)
   for (let element of elements) {
    element.dispatchEvent(evObj)
   }
   let errorInputs = document.getElementsByClassName('input-error');
   if(errorInputs.length === 0){
    vNode.context.submit();
   }
  })
 }
})

<template>
 <div>
  <div>
  <label class="star">Name:</label>
   <input class='v-check' v-checkParam="{required:true,regex:'^[abcde]*$'}" type="text">
  </div>
  <div>
  <label class="star">IP:</label>
   <input class='v-check' v-checkParam="{required:true,regex:'IpRegex'}"
   type="text">
   </div>
  <div>
   <button v-checkSubmit>提交</button>
  </div>
 </div>
</template>
<script>
export default {
 name: 'demo',
 methods: {
  submit () {
   alert('通过校验')
  }
 }
}
</script>

<style scoped>
input{
  height: 22px;
}
.input-error{
 background-color: red;
}
.star:before
{
 content:"*";
 color:red;
}
</style>