WPF - 来自用户控件内部的事件

时间:2011-03-21 14:45:08

标签: c# wpf events wpf-controls

尝试在WPF中为自定义控件创建事件时遇到问题。我们的代码如下:


public static readonly RoutedEvent KeyPressedEvent =
            EventManager.RegisterRoutedEvent(
                "keyPressed", RoutingStrategy.Bubble,
                    typeof(KeyEventHandler), typeof(Keyboard));

    public event KeyEventHandler keyPressed
    {
        add { AddHandler(KeyPressedEvent, value); }
        remove { RemoveHandler(KeyPressedEvent, value); }
    }

void btnAlphaClick(object sender, RoutedEventArgs e)
    {
        var btn = (Button)sender;
        Key key = (Key)Enum.Parse(typeof(Key), btn.Content.ToString().ToUpper());
        PresentationSource source = null;
        foreach (PresentationSource s in PresentationSource.CurrentSources)
        {
            source = s;
        }
        RaiseEvent(new KeyEventArgs(InputManager.Current.PrimaryKeyboardDevice, source,0,key));

控件是一个屏幕键盘,我们基本上需要传递给KeyPressedEventArgs给事件的订阅者详细说明按下了什么键(我们找不到太多帮助我们在WPF中使用它,只有winforms)

任何帮助,非常感谢!

1 个答案:

答案 0 :(得分:7)

步骤1:将事件处理程序添加到“确定”和“取消”按钮

private void btnOK_Click(object sender, RoutedEventArgs e)
{     
}

private void btnCancel_Click(object sender, RoutedEventArgs e)
{     
}

在UserControl1.xaml.cs文件中添加公共属性以与主机共享文本框的值

public string UserName
{
    get { return txtName.Text; }
    set { txtName.Text = value; }
}

声明可以通过Windows窗体订阅的Ok和Cancel按钮的事件。

public event EventHandler OkClick;
public event EventHandler CancelClick;

现在将代码添加到事件处理程序中,以便我们也可以将事件提升为托管。

private void btnOK_Click(object sender, RoutedEventArgs e)
{
    if (OkClick != null)
        OkClick(this, e);
}

private void btnCancel_Click(object sender, RoutedEventArgs e)
{
    if (CancelClick != null)
        CancelClick(this, e);
}

第2步:在Windows窗体中处理WPF控件事件

在创建用户控件实例后立即将Handler添加到OKClickCancelClick个事件

_WPFUserControl.OkClick += new EventHandler(OnOkHandler);
_WPFUserControl.CancelClick += new EventHandler(OnCancelHandler);

在处理程序方法中编写代码。在这里,我在OK按钮处理程序中使用UserName属性,以便显示如何共享值。

protected void OnOkHandler(object sender, EventArgs e)
{
    MessageBox.Show("Hello: " +_WPFUserControl.UserName + " you clicked Ok Button");
}

protected void OnCancelHandler(object sender, EventArgs e)
{
    MessageBox.Show("you clicked Cancel Button");
}

参考: http://a2zdotnet.com/View.aspx?Id=79