FluentValidation 向 WithMessage 传递参数

Question

我在验证器中有以下代码：

RuleFor(mb => mb.Amount).
Must((mb, amount) =>
                {
                   var betLimit = _battlesService.GetBetLimit(mb.BattleId);

                   mb.Amount <= betLimit;
                }).
WithMessage("Bet should be less than {0}", "bet limit value should be placed here");

有什么方法可以将betLimit值传递给WithMessage方法吗？我看到的唯一解决方案是将betLimit 值设置为ViewModel 的某些属性，然后在WithMessage 重载中使用funcs 访问它。但它很丑。

Answer 1

由于

Amount

不用于获取

betLimit

，您不能在验证器启动时将下注限制拉入一个字段，并在任何您想要的地方使用它吗？ 比如：

public ViewModelValidator(IBattlesService battlesService)
{
    var betLimit = battlesService.GetBetLimit();

    RuleFor(mb => mb.Amount).
    Must((mb, amount) =>
                    {
                       mb.Amount <= betLimit;
                    }).
    WithMessage(string.Format("Bet should be less than {0}", "bet limit value should be placed here", betLimit));
    ...
}

更新：

我现在看到您从视图模型添加了参数。 根据 FluentValidation 文档中的第三个示例，您应该能够像这样访问它：

    public ViewModelValidator(IBattlesService battlesService)
    {
        RuleFor(mb => mb.Amount).
        Must((mb, amount) =>
                        {
                           mb.Amount <= betLimit;
                        }).
        WithMessage("Bet should be less than {0}", mb => battlesService.GetBetLimit(mb.BattleId));
        ...
    }

Answer 2

https://docs.fluidation.net/en/latest/custom-validators.html#custom-message-placeholders

RuleFor(mb => mb.Amount).
Must((mb, amount, context) =>
{
  var betLimit = _battlesService.GetBetLimit(mb.BattleId);
  context.MessageFormatter.AppendArgument("BetLimit", betLimit );
  mb.Amount <= betLimit;
}).
WithMessage("Bet should be less than {BetLimit}");