第一步写好表单，并在表单中绑定校验表:rules=“rule”

<el-form class="apply-form first-form" :model="formData" :rules="rule" ref="form">
    <el-form-item label="姓名" prop="visitorName">
        <el-input v-model="formData.visitorName" placeholder="请输入姓名" clearable></el-input>
    </el-form-item>
    <el-form-item label="身份证号" prop="cardCode">
       <el-input v-model="formData.cardCode" :maxlength="18" placeholder="请输入身份证号" clearable></el-input>
    </el-form-item>
</el-form>

第二步在data()中填写表单校验规则，对应的校验字段要在prop中填写
如prop=“visitorName”，然后在rule{}中写上验证规则
具体校验参数规格参考https://github.com/yiminghe/async-validator

data() {
   return {
       formData: {
           visitorName: '',
           cardType: 1,
           cardCode: ''
       },
       rule: {
           visitorName: [
               { required: true, message: '请输入姓名', trigger: 'blur' },
               { min: 2, max: 10, message: '长度在 2 到 10 个字符', trigger: 'blur' },
               {
                        required: true,
                        pattern: /^[\u4e00-\u9fa5_a-zA-Z0-9.·-]+$/,
                        message: '姓名不支持特殊字符',
                        trigger: 'blur'
               }
          ],
          cardCode: [
              { required: true, message: '请输入身份证号', trigger: 'blur' },
              { min: 15, max: 18, message: '请如实填写18位号码，以供学校保卫科核对', trigger: 'blur' },
              {
                   required: true,
                   pattern: /(^\d{15}$)|(^\d{18}$)|(^\d{17}(\d|X|x)$)/,
                   message: '请输入正确的身份证号码',
                   trigger: 'blur'
              }
          ]
      }
   }
}

第三步可自定义校验规则，将校验规则写在data()中

data() {
    let reg = /(?!^(\d+|[a-zA-Z]+|[~!@#$%^&*?]+)$)^[\w~!@#$%^&*?]{6,12}$/
    var validateNewPwd = (rule, value, callback) => {
        if (!reg.test(value)) {
            callback(new Error('密码应是6-12位数字、字母或字符！'))
        } else if (this.form.oldPasswd === value) {
            callback(new Error('新密码与旧密码不可一致！'))
        } else {
            callback()
        }
    }
    var validateComfirmPwd = (rule, value, callback) => {
        if (!reg.test(value)) {
            callback(new Error('密码应是6-12位数字、字母或字符！'))
        } else if (this.form.newPasswd !== value) {
            callback(new Error('确认密码与新密码不一致！'))
        } else {
            callback()
        }
    }
    return {
        form: {
            newPasswd: '',
            comfirmPwd: ''
        },
        rules: {
            newPasswd: [
                { required: true, message: '请输入新密码', trigger: 'blur' },
                { validator: validateNewPwd, trigger: 'blur' }
            ],
            comfirmPwd: [
                { required: true, message: '请输入确认密码', trigger: 'blur' },
                { validator: validateComfirmPwd, trigger: 'blur' }
            ]
        }
    }
}