1.要求

    在做一些用户信息相关的功能时，经常用到表单项去收集数据，其中有些属性必须填写，

2.实现方法

在data中添加一个rules来规定：

rules: {
    no: [{required: true, message: '请输入账号', trigger: 'blur'}]
}

其中：required表示是否为必填项；message:表示提示信息；trigger：表示失去焦点时验证
这一句可以在表单必填项前面添加红色*和提示信息

   2.在el-form表单中绑定rules：

<el-form ref="form" :model="form" :rules="rules"></el-form>

    3.在表单项中用prop属性来对应el-form的:rules="rules"

这一步很重要，

<el-form-item class="item" prop="no" label="登陆账号">
          <el-input v-model="form.no"></el-input>
</el-form-item>

3.完整代码

//<template>
<div>
    <div class="title">用户设置</div>
      <el-form ref="formdata" :model="formdata" :rules="rules" label-width="78px">
        <el-form-item class="item" prop="no" label="登陆账号">
          <el-input v-model="formdata.no" disabled></el-input>
        </el-form-item>
        <el-form-item class="item" prop="name" label="用户名称">
          <el-input v-model="formdata.name" disabled></el-input>
        </el-form-item>
        <el-form-item class="item" prop="oldPsw" label="原始密码">
          <el-input v-model="formdata.oldPsw" show-password  placeholder="请输入原始密码" ></el-input>
        </el-form-item>
        <el-form-item class="item" prop="newPsw" label="新密码">
          <el-input v-model="formdata.newPsw" show-password  placeholder="请输入新密码"></el-input>
        </el-form-item>
        <el-form-item class="item" prop="retypePsw" label="确认密码">
          <el-input v-model="formdata.retypePsw" show-password  placeholder="请再次输入新密码"></el-input>
        </el-form-item>
        <el-form-item>
          <el-button type="primary" @click="onSubmit">确认</el-button>
          <el-button>取消</el-button>
        </el-form-item>
      </el-form>
</div>
//data
data()
  {
    return {
      formdata: {
        no: user.no,
        name: user.name,
        oldPsw: '',
        newPsw: '',
        retypePsw: ''
      },
      rules:
      {
        no: [{required: true, message: '请输入账号', trigger: 'blur'}],
        name: [{required: true, message: '请输入用户姓名', trigger: 'blur'}],
        oldPsw: [{required: true, message: '请输入密码', trigger: 'blur'}],
        newPsw: [
          {required: true, message: '请输入新密码', trigger: 'blur'}],
        retypePsw: [
          { required: true, message: '请再次输入密码', trigger: 'blur' }]
      }
    }
  }

4，表单校验

handleAddDeploy() {
      this.$refs.formLabelAlign.validate(async valid => {
        if (!valid) return false;
        if (this.addFlag) {
          // 新增
          this.formLabelAlign = dataAddDefalutTime(this.formLabelAlign);
          this.addDeploy();
        } else if (this.updateFlag) {
          // 修改
          this.updateDeploy();
        } else if (this.reviewFlag) {
          // 审核
          this.reviewDeploy();
        } else if (this.apperoveFlag) {
          // 审批
          this.apperoveDeploy();
        }
      });
    },

5，另一种校验，更加简洁

rules: {
        externalSupportPlace: [
          // 对外支援服务区域
          {
            required: true,
            validator: this.validationExternalSupportPlace,
            trigger: 'blur'
          }
        ],
        firstPhone: [
          {
            required: false,
            trigger: 'blur'
          },
          {
            // pattern: /^0{0,1}(13[0-9]|15[7-9]|153|156|18[7-9])[0-9]{8}$/,
            pattern: phone_regular,
            message: '手机号格式不对',
            trigger: 'blur'
          }
        ]
}

validationExternalSupportPlace(rule, value, callback) {
      this.$nextTick(() => {
        if (this.dataForm.externalSupport === 1 && !this.dataForm.externalSupportPlace) {
          return callback(new Error('请输入对外支援服务区域'))
        } else {
          callback()
        }
      })
    },