从数据库获取数据并将其添加到文本框C＃wpf

Question

为什么我在运行程序时在文本框中什么也没得到？我在课堂上有我的方法，谁能给我任何提示，我可以解决这个问题。

MainWin代码

   *List<Card> cards = new List<Card>();

    DBManager dB = new DBManager();
    public MainWindow()
    {
        Card card = new Card();

        InitializeComponent();
        dB.GetCards(cards);
        txtQuestion.Text = card.Question;
        lblCardsList.ItemsSource = cards;
        GetRandomCards();
        DisplayCardQuestion();

    }

    private void GetRandomCards()
    {
        Card card = new Card();
        Random random = new Random();
        int rndCard = random.Next(1, 100);
        for (int i = 0; i < rndCard; i++)
        {
           cards.Add(card);
        }


    }
    private void DisplayCardQuestion()
    {
        Card card = new Card();

            lblCardNum.Content =card.CardID;
            txtQuestion.Text = card.Question;
            txtTitle.Text = card.Title;

       }*

Answer 1

您从数据库获取卡，但未将其分配给任何变量