在VB.net中绑定WPF按钮单击的正确方法是什么

Question

I am trying to figure out how I should bind the click action of a button in vb.net for WPF

Here is a section of WPF code

WPF:

<TabItem Name="tab_emailSender>
    <TextBox Text="{Binding Path=address}" />
    <Button Command="{Binding Path=sendTestMessage}"
</TabItem>

VB

Class MainWindow
    Dim thisMessage as new Message

    Private Sub main() Handles Me.Loaded
        tab_emailSender.DataContext = thisMessage
    End Sub
End Class

Class Message
   Public Property address as string

   Public Sub sendTestMessage()
       msgbox("it worked!")
   End Sub
End Class

I am able to bind the textbox's text but I am not sure how to bind the button's click event to the sendTestMessage sub.

Answer 1

In order to handle the button's click event, if you want to follow MVVM, you need to create an ICommand property on your ViewModel. ICommand is the inteface, so you can do something like this (sorry for C#):

public class Message: ICommand
{
    public address { get; set; }


    public bool CanExecute(Object parameter)
    {
        return true; 
    }
    public void Execute(Object parameter)
    {
        //Do the logic here.
    }
}

and the xaml (as far as your DataContext is the instance of Message type):

<Button Command="{Binding}" />

Of course you can implement the interface by yourself, on another class, etc. (I've made the implementation inside the Message class because its simplier here), but you can also find useful to use DelegateCommand or RelayCommand . This classes will prevent you from re-implementing the interface involved every time you need the new command.