How to close all the windows when Mainwindow closes

Question

I am working on WPF. There is Mainwindow which opens as application starts. There are two buttons within this window. Each open a new window. e.g There are Add and update buttons. Add button opens a Add-Item window on its click event call and similarly update opens it's window "Update-Item". If i close Mainwindow these two windows "Add-Item" and "Update-Item" remains open. I want that if i close Mainwindow, these other two windows should also close with it.

app.current.shutdown

app.current.shutdown is used mostly. My Question is: Where i have to post this code line in my program, in mainwindow or in App.config. Should i have to call any event or function in it's response too?

Answer 1

You can also set ShutdownMode in the App.xaml file:

<Application x:Class="WpfApp1.App"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:WpfApp1"
    StartupUri="MainWindow.xaml"
    ShutdownMode="OnMainWindowClose">
    <Application.Resources>
    </Application.Resources>
</Application>