使用RoutedEventArgs传递变量？

Question

我有以下类,并希望将文本变量作为RoutedEventArgs传递.

  public class CloseableTabItem : TabItem
  {
    String text;

    public CloseableTabItem()
    {
      //This style is defined in themes\generic.xaml
      DefaultStyleKeyProperty.OverrideMetadata(typeof(CloseableTabItem),
          new FrameworkPropertyMetadata(typeof(CloseableTabItem)));
    }

    public CloseableTabItem(String incomingText)
    {
      //This style is defined in themes\generic.xaml
      DefaultStyleKeyProperty.OverrideMetadata(typeof(CloseableTabItem),
          new FrameworkPropertyMetadata(typeof(CloseableTabItem)));
      text = incomingText;
    }

    public static readonly RoutedEvent CloseTabEvent =
        EventManager.RegisterRoutedEvent("CloseTab", RoutingStrategy.Bubble,
            typeof(RoutedEventHandler), typeof(CloseableTabItem));

    public event RoutedEventHandler CloseTab
    {
      add { AddHandler(CloseTabEvent, value); }
      remove { RemoveHandler(CloseTabEvent, value); }
    }

    public override void OnApplyTemplate()
    {
      base.OnApplyTemplate();

      Button closeButton = base.GetTemplateChild("PART_Close") as Button;
      if (closeButton != null)
        closeButton.Click += new System.Windows.RoutedEventHandler(closeButton_Click);
    }

    void closeButton_Click(object sender, System.Windows.RoutedEventArgs e)
    {
      this.RaiseEvent(new RoutedEventArgs(CloseTabEvent, this));
    }
  }

这是来自Window1的代码,它是WPF应用程序中的主要类

  public partial class Window1 : Window
  {
    public static Window1 myWindow1;

    public Window1()
    {
      myWindow1 = this;
      InitializeComponent();
      this.AddHandler(CloseableTabItem.CloseTabEvent, new RoutedEventHandler(this.CloseTab));
    }

    private void CloseTab(object source, RoutedEventArgs args)
    {
      TabItem tabItem = args.Source as TabItem;
      if (tabItem != null)
      {
        TabControl tabControl = tabItem.Parent as TabControl;
        if (tabControl != null)
          tabControl.Items.Remove(tabItem);
      }
    }

    private void btnAdd_Click(object sender, RoutedEventArgs e)
    {
      CloseableTabItem tabItem = new CloseableTabItem("THIS IS A TEST");
      MainTab.Items.Add(tabItem);
    }
  }

我希望能够在CloseTab方法中打印"String text"的值.如何使用RoutedEventArgs args传递"String text"？

最好的祝福!

编辑

我对项目进行了一些更改,这是代码

ClosableTabItem.cs

namespace SampleTabControl
{
  public class CloseableTabItem : TabItem
  {

    String text;
    public delegate void TabsEventHandler(object sender, TabsEventArgs e);

    public CloseableTabItem()
    {
      //This style is defined in themes\generic.xaml
      DefaultStyleKeyProperty.OverrideMetadata(typeof(CloseableTabItem),
          new FrameworkPropertyMetadata(typeof(CloseableTabItem)));
    }

    public CloseableTabItem(String incomingText)
    {
      //This style is defined in themes\generic.xaml
      DefaultStyleKeyProperty.OverrideMetadata(typeof(CloseableTabItem),
          new FrameworkPropertyMetadata(typeof(CloseableTabItem)));
      this.text = incomingText;
    }

    public static readonly RoutedEvent CloseTabsEvent = EventManager.RegisterRoutedEvent("CloseTab", RoutingStrategy.Bubble, typeof(TabsEventHandler), typeof(CloseableTabItem));    

    public event TabsEventHandler CloseTab
    {
      add { AddHandler(CloseTabsEvent, value); }
      remove { RemoveHandler(CloseTabsEvent, value); }
    }


    public override void OnApplyTemplate()
    {
      base.OnApplyTemplate();

      Button closeButton = base.GetTemplateChild("PART_Close") as Button;
      if (closeButton != null)
        closeButton.Click += new System.Windows.RoutedEventHandler(closeButton_Click);
    }

    void closeButton_Click(object sender, System.Windows.RoutedEventArgs e)
    {
      TabsEventArgs args = new TabsEventArgs(CloseTabsEvent, text);
      RaiseEvent(args);
    }
  }
}

TabsEventArgs.cs

public class TabsEventArgs : RoutedEventArgs
{
    private readonly string text;

    public string Text
    {
        get { return text; }
    }

    public TabsEventArgs(RoutedEvent routedEvent, string text) : base(routedEvent)
    {
        this.text = text;
    }
}

Window1.cs

  public partial class Window1 : Window
  {
    public static Window1 myWindow1;

    public Window1()
    {
      myWindow1 = this;
      InitializeComponent();
      this.AddHandler(CloseableTabItem.CloseTabsEvent, new RoutedEventHandler(this.CloseTab));
    }

    private void CloseTab(object source, RoutedEventArgs args)
    {      
      TabItem tabItem = args.Source as TabItem;
      if (tabItem != null)
      {
        TabControl tabControl = tabItem.Parent as TabControl;
        if (tabControl != null)
          tabControl.Items.Remove(tabItem);
      }
    }

    private void btnAdd_Click(object sender, RoutedEventArgs e)
    {
      CloseableTabItem tabItem = new CloseableTabItem("THIS IS A TEST");
      MainTab.Items.Add(tabItem);
    }
  }

进行更改后(当我打开超过1个选项卡时,应用程序崩溃),您将如何访问Window1类中的CloseTab方法中的"字符串文本"？

Answer 1

创建一个新的子类RoutedEventArgs,向其添加一个属性,您可以在其中存储要传递的变量,并创建一个相应的类型的处理程序委托,void (object, YourNewEventArgs)然后将其指定为事件的处理程序类型(当前使用的是法线RoutedEventHandler,因此只提供正常的RoutedEventArgs).

如果要引发事件,则需要创建新事件args并将变量传递给该变量的属性.如何在处理程序中获取值应该是不言自明的.

Answer 2

我需要类似的东西,在@Arya和@HB的帮助下,我想出了这个:

我的自定义RoutedEventArgs子类

public class ChangePageEventArgs : RoutedEventArgs {
    private readonly int _pageNumber;

    public int PageNumber {
        get { return _pageNumber; }
    }

    public ChangePageEventArgs(RoutedEvent routedEvent, int pageNumber) : base(routedEvent) {
        this._pageNumber = pageNumber;
    }
}

我的孩子班

private void defineButton_Click(object sender, RoutedEventArgs e) {
    ChangePageItemList(2);
}

public static readonly RoutedEvent GoToItemPropertiesViewEvent = EventManager.RegisterRoutedEvent(
"GoToItemPropertiesView", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(NoObjectView));

// Provide CLR accessors for the event
public event RoutedEventHandler GoToItemPropertiesView {
    add { AddHandler(GoToItemPropertiesViewEvent, value); }
    remove { RemoveHandler(GoToItemPropertiesViewEvent, value); }
}

public void ChangePageItemList(int _pageNumber) {
    ChangePageEventArgs args = new ChangePageEventArgs(GoToItemPropertiesViewEvent, _pageNumber);
    this.RaiseEvent(args);
}

我的父班

private ItemListView createItemListView() {
    _itemListView = new ItemListView();
    _itemListView.GoToItemPropertiesView += new RoutedEventHandler(ChangePage);

    return _itemListView;
}

private void ChangePage(object sender, RoutedEventArgs e) {
    ChangePageEventArgs args = (ChangePageEventArgs)e;
    // Value of page number is 2
    int _pageNumber = args.PageNumber;
}

希望它能帮助你@Arya