vant(ZanUi)结合async-validator实现表单验证的方法

import asyncValidator from 'async-validator'

class validator {
 /**
 * 构造
 * @param rules object async-validator rules
 * @param data 初始对象
 */
 constructor(rules, data) {
 this.setData(data);
 this.setRules(rules);
 }

 /**
 * 重新定义初始对象
 * 也可以直接修改实例的data
 * validator.data = newData
 * @param data
 */
 setData(data) {
 this.data = data;
 }

 /**
 * 设定规则
 * @param rules rules object async-validator rules
 * @param cover 是否替换旧规则
 */
 setRules(rules, {cover} = {}) {
 if (cover === undefined || cover) {
  this.validators = {};
 }
 for (let attr in rules) {
  const rule = {};
  rule[attr] = rules[attr];
  this.validators[attr] = new asyncValidator(rule);
 }
 }

 /**
 * 执行验证
 * @param callback(errors, fields)
 * @param data 可选 传空将验证构造data 传string或数组验证构造data的响应字段
 * 以上参数顺序可互转
 */
 validate(callback, data) {
 let cb,d;
 if (typeof callback === 'function' ){
  cb = callback;
  d = data;
 }else if (typeof data === 'function' ){
  cb = data;
  d = callback;
 }

 let _d = d;

 if (this.data) {
  if (!d) {
  _d = this.data;
  } else if (typeof d === 'string') {
  _d = {};
  _d[d] = this.data[d]
  } else if (Array.isArray(d)) {
  _d = {};
  d.forEach(attr => {
   _d[attr] = this.data[attr]
  })
  }
 }

 const err = [];

 if (_d) {
  for (let attr in _d) {
  if (this.validators[attr]) {
   const o = {};
   o[attr] = _d[attr];
   this.validators[attr].validate(o, (error) => {
   if (error) {
    err.push(error[0])
   }
   })
  }
  }
 }

 cb && cb(err.length > 0, err)

 }
}

export default function (rules, data) {
 return new validator(rules, data)
}