如何在没有计数的代码中获得“计数不能小于零”异常？

Question

    public void ABtn()
    {
        if (ABtnState == "E")
        {
            phrase.Points += -(int)Settings.ABtn;
            ABtnState = "D";
        }
        else
        {
            phrase.Points += (int)Settings.ABtn;
            ABtnState = "E";
        }
        if (BBtnState == "E")
        {
            phrase.Points += -(int)Settings.BBtn;
            BBtnState = "D";
        }
        if (CBtnState == "E") { phrase.Points += -(int)Settings.CBtn; CBtnState = "D"; }
        if (DBtnState == "E") { phrase.Points += -(int)Settings.DBtn; DBtnState = "D"; }
        if (EBtnState == "E") { phrase.Points += -(int)Settings.EBtn; EBtnState = "D"; }
        App.DB.SetPoints(phrase.PhraseId, phrase.Points);
        App.viewablePhrases = App.DB.GetViewablePhrases(Settings.Mode, Settings.Pts, true);
        Cif2aInfo = new String('☆', phrase.Points);
    }

有人知道是什么导致了这个问题吗？或者我该如何纠正这个问题？

Answer 1

来自Microsoft文档：

String（Char c，Int32 count）将新实例初始化为由重复指定次数的指定Unicode字符指示的值

因此，如果您的短语。点小于0，它将跟踪您的错误，请在C#Online编译器中尝试以下操作：

string Cif2aInfo = new String('☆', -1);
Console.WriteLine(Cif2aInfo);

Cif2aInfo = phrase.Points != null && phrase.Points > 0 ? new String('☆', phrase.Points) : string.Empty;