html

<el-dialog
  title="提示"
  :visible.sync="addVisible"
  width="50%"
  @close="addDialogClose">
  <el-form ref="addFormRef" :model="addForm" :rules="addFormRules"  label-width="80px">
    <el-form-item label="用户名" prop="username">
      <el-input v-model="addForm.username"></el-input>
    </el-form-item>
    <el-form-item label="密码" prop="password">
      <el-input v-model="addForm.password"></el-input>
    </el-form-item>
    <el-form-item label="邮箱" prop="email">
      <el-input v-model="addForm.email"></el-input>
    </el-form-item>
    <el-form-item label="手机" prop="mobile">
      <el-input v-model="addForm.mobile"></el-input>
    </el-form-item>
  </el-form>
  <span slot="footer" class="dialog-footer">
    <el-button @click="addVisible = false">取 消</el-button>
    <el-button type="primary" @click="addUser">确 定</el-button>
  </span>
</el-dialog>

js

var checkEmail = (rules, value, callback) => {
  if(!value){
    return callback(new Error('邮箱不能为空'));
  }
  const regEmail = /^[a-zA-Z0-9_-]+@[a-zA-Z0-9_-]+(\.[a-zA-Z0-9_-]+)+$/
  if(regEmail.test(value) == false){
    return callback(new Error('邮箱格式有误'));
  }
}