Question

我正在尝试编写一个简单的按钮，当您单击它时，它会添加1并更新标签，但仅在第一次单击时起作用，此后它将不再更新标签。

    protected void Page_Load(object sender, EventArgs e)
    {   }


    protected void ClickerButton_Click(object sender, ImageClickEventArgs e)
    {

            Lbl_PairsCooked.Text = CookSneaker(NumOfPairs).ToString();

    }

    public int CookSneaker(int num)
    {
        num += 1;
        return num;
    }

我制作的图像按钮仅在第一次单击时起作用...

Answer 1

有关如何使其正常工作，请参见下面的代码段。最重要的是，您需要在IsPostBack上阅读链接 https://docs.microsoft.com/en-us/dotnet/api/system.web.ui.page.ispostback?view=netframework-4.8了解区别。

  public partial class _Default : Page
    {
        int NumOfPairs;
        protected void Page_Load(object sender, EventArgs e)
        {
            if (IsPostBack)
            {
                //this line reads the text from label, converts and assigns to NumPairs. The UI is updated on the button click which takes this new NumOfPairs.
                int.TryParse(Label1.Text, out NumOfPairs);                                
            }
        }

        protected void Button1_Click(object sender, EventArgs e)
        {
            Label1.Text = CookSneaker(NumOfPairs).ToString();
        }

        public int CookSneaker(int num)
        {
            num += 1;
            return num;
        }

    }

基本增量按钮单击

1 个答案: