小编jay*_*rio的帖子

我目前正在使用 asp .net core 学习 vuejs。我正在做一些表单验证并添加一些错误消息。

错误消息来自服务器端，这里是我的示例代码：

 [HttpPost]
    public async Task<IActionResult> AddUser([FromBody] UserModel user)
    {

        if (!ModelState.IsValid)
        {
            return BadRequest(ModelState);
        }

        if (_context.Users.Any(u => u.UserName == user.UserName))
        {
            ModelState.AddModelError("UserName", "Username is already in used");
            return BadRequest(ModelState);
        }

        try
        {
            var userDto = new User
            {
                FirstName = user.FirstName,
                LastName = user.LastName,
                Password = user.Password,
                UserName = user.UserName
            };
            _context.Users.Add(userDto);
            await _context.SaveChangesAsync();
        }
        catch(Exception e)
        {
            ModelState.AddModelError("Saving Error", string.Format("Error in saving user. \nDetails:\n {0}", e.Message));
            return BadRequest(ModelState);
        }

        return Ok();
    } …