学步园

Send event to Host (Windows Form) from a WPF Control - Part 1

In this article you would see how event from WPF control could be passed to hosting windows form. To raise the event to back to host I am not creating the custom event, rather I would use standard .NET event handler.  I
explained how to host a WPF control into the Windows Form in the one of my previous article.

Step1. Add Event Handler to Ok and Cancel Button:

1. Open WpfUserControlLib project in Visual Studio 2008.
   
2. Add the Event Handler for the btnOk and btnCancl button in the WPF Library 

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

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

3. Add the public property in the UserControl1.xaml.cs file to share the value of the textbox with the host

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

4. Declare the Events for Ok and Cancel Buttons which can be subscribed by Windows Form.

public event EventHandler OkClick;
public event EventHandler CancelClick;

5. Now add the code to the event handler so that we can raise the event to host also.

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);
}

Step 2: Handle the WPF Control Event in Windows Form:

1. Add Handler to OKClick and Cancel click Event just after creating the instance of the user control.      
   

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

2. Write code in the handler method. Here I user the UserName property in the OK button handler so show the how to share the values also.

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");
}

Compile and Run the Windows Application you would see the WPF control is hosted in the Windows Control, Enter your name in the Text box and click OK and Cancel Button to see you are getting back the event from WPF control. 

Summary: We can use the power of the WPF Control’s visual elements into the Windows Form application by hosting very easily. You can share the data and send the event to host from the WPF control. In Part
2 I would explain how to use custom arguments and custom events.

转自【http://www.a2zdotnet.com/View.aspx?Id=79#.Ub8fZZyvy3I】