Element UI 自定义Validator

我们可以在formitem上指定验证规则，有时候我们需要校验用户数据的值是否有效，这时候就需要用到自定义的validator

<el-form ref="form" :model="form" :rules="rules" label-width="260px">

rule的写法如下，这里分别加了必填验证，数字格式验证（使用的正则表达式），自定义校验：

rules: {
          ClientNumber: [
            {
              required: true,
              message: 'The client number cannot be empty',
              trigger: 'blur',
            },
            {
              type: 'string',
              pattern: /^[A-Za-z0-9]{1,25}$/,
              message:
                'Client number should be a number or letter with maximum length of 25.',
              trigger: 'blur',
            },
            {
              validator: ClientNumberValidator,
              trigger: 'blur',
            },
          ],
        },

自定义方法的写法：

export default {
    ...
    data() {
      var ClientNumberValidator = async (rule, value, callback) => {
          const { code, data } = await checkClientNumberExists({
            param1: value1,
            param2: value2,
          })
          if (code && code === 200 && data == true) {
            callback(
              new Error(
                'The Number has already been used .'
              )
            )
        }
      }
      return {
     ...