elementUI中 form表单自定义验证方法

<template>
<el-form :model="ruleForm" :rules="dataRule" ref="dataForm" @keyup.enter.native="dataFormSubmit()" label-width="130px">
  <el-form-item label="类型名称" prop="drinkCategoryName">
    <el-input v-model="dataForm.drinkCategoryName" placeholder="请输入饮品类型名称"></el-input>
  </el-form-item>
  <el-form-item label="年龄" prop="age">
	<el-input v-model.number="ruleForm.age"></el-input>
  </el-form-item>
  <el-form-item label="密码" prop="pass">
    <el-input type="password" v-model="ruleForm.pass" auto-complete="off"></el-input>
  </el-form-item>
  <el-form-item label="确认密码" prop="checkPass">
    <el-input type="password" v-model="ruleForm.checkPass" auto-complete="off"></el-input>
  </el-form-item>
</el-form>
</template>

<script>
  export default {
    data() {
      //判断类型名称是否重复
      var validatePass = (rule, value, callback) => {
        let params = {
          name: value
        }
        this.$api.get(url),params).then(res => {
          if(res && res.data.code === 0){
            callback() //验证通过
          }else{
           callback(new Error('名称不能重复哦~')) //没有验证通过
          }
        })
      }
      var checkAge = (rule, value, callback) => {
        if (!value) {
          return callback(new Error('年龄不能为空'));
        }
        setTimeout(() => {
          if (!Number.isInteger(value)) {
            callback(new Error('请输入数字值'));
          } else {
            if (value < 18) {
              callback(new Error('必须年满18岁'));
            } else {
              callback();
            }
          }
        }, 1000);
      };
      var validatePass = (rule, value, callback) => {
        if (value === '') {
          callback(new Error('请输入密码'));
        } else {
          if (this.ruleForm.checkPass !== '') {
            this.$refs.ruleForm.validateField('checkPass');
          }
          callback();
        }
      };
      var validatePass2 = (rule, value, callback) => {
        if (value === '') {
          callback(new Error('请再次输入密码'));
        } else if (value !== this.ruleForm.pass) {
          callback(new Error('两次输入密码不一致!'));
        } else {
          callback();
        }
      };
      return {
        ruleForm: {
          drinkCategoryName: '',
          pass: '',
          checkPass: '',
          age: ''
        },
        dataRule: {
          drinkCategoryName: [
            { required: true, message: '类型名称不能为空', trigger: 'blur' },
            { validator:validatePass,trigger:'blur'}
          ],
          pass: [
            { validator: validatePass, trigger: 'blur' }
          ],
          checkPass: [
            { validator: validatePass2, trigger: 'blur' }
          ],
          age: [
            { validator: checkAge, trigger: 'blur' }
          ]
        }
      };
    },
    methods: {
    // 表单提交
      dataFormSubmit () {
        this.$refs['dataForm'].validate((valid) => {
          if (valid) {
            this.getInit()
          } else {
            console.log('error submit!!');
            return false;
          }
        })
      }
	}
  }
</script>

单独验证表单中某一项

if (!this.ruleForm.mobile) {
    this.$refs.ruleForm.validateField('mobile')
    return false
}