capture close function

PacticeSolution/Capture/MainWindow.xaml

@@ -20,6 +20,14 @@
         </Grid.RowDefinitions>
         <Border BorderThickness="{Binding FrameThickness}" BorderBrush="{Binding FrameColor}"/>
 
-        <Button x:Name="btnCapture" Grid.Row="1" Content="Capture" Click="btnCapture_Click"/>
+        <Grid Grid.Row="1">
+            <Grid.ColumnDefinitions>
+                <ColumnDefinition Width="{Binding CloseButtonWidth}"/>
+                <ColumnDefinition Width="*"/>
+            </Grid.ColumnDefinitions>
+
+            <Button x:Name="btnClose" Grid.Column="0" Content="❎" Click="btnClose_Click"/>
+            <Button x:Name="btnCapture" Grid.Column="1" Content="Capture" Click="btnCapture_Click"/>
+        </Grid>
     </Grid>
 </Window>

PacticeSolution/Capture/MainWindow.xaml.cs

@@ -80,5 +80,10 @@ namespace Capture
 
             this.DragMove();
         }
+
+        private void btnClose_Click(object sender, RoutedEventArgs e)
+        {
+            Application.Current.Shutdown();
+        }
     }
 }

PacticeSolution/Capture/OptionContext.cs

@@ -10,6 +10,7 @@ namespace Capture
     public class OptionContext
     {
         public int ButtonHeight { get; set; } = 20;
+        public int CloseButtonWidth { get; set; } = 20;
         public Brush FrameColor { get; set; } = Brushes.Red;
         public int FrameThickness { get; set; } = 2;
     }