GotFocus for a grid

Instead of having one GotFocus-trigger for each textbox in a grid, you can have it at Grid-level.

XAML:

<Window x:Class="Test.Window1"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        >
       <Grid GotFocus="Grid_GotFocus" LostFocus="Grid_LostFocus">
             <TextBox Height="23" Margin="12,12,12,0" x:Name="textBox1" VerticalAlignment="Top" />
             <TextBox Margin="12,41,12,0" x:Name="textBox2" Height="23" VerticalAlignment="Top" />
       </Grid>
</Window>

Codebehind:

using System.Windows;
using System.Windows.Controls;

namespace Test {
  /// <summary>
  /// Interaction logic for Window1.xaml
  /// </summary>
  public partial class Window1 : Window  {
         public Window1() { InitializeComponent(); }
                private void Grid_GotFocus( object sender , RoutedEventArgs e ) {
                        if ( e.Source is TextBox ) {
                            TextBox t = e.Source as TextBox;
                            MessageBox.Show( t.Name + " Got focus" );
                        }
                }
                private void Grid_LostFocus( object sender , RoutedEventArgs e ) {
                        if ( e.Source is TextBox ) {
                            TextBox t = e.Source as TextBox;
                            MessageBox.Show( t.Name + " Lost focus" );
                        }
                }
        }
}

Useful for validations.

For example – if you want to process names and values of all textboxes as soon as user is leaving a textbox, you can in the LostFocus eventhandler do this:

        private void Grid_LostFocus( object sender , RoutedEventArgs e )  {
            if ( e.Source is TextBox )   {
                int count = VisualTreeHelper.GetChildrenCount(theGrid);
                string u = string.Empty;
                for ( int i = 0; i < count; i++ )      {
                      object o = VisualTreeHelper.GetChild( theGrid , i );
                      if ( o is TextBox ) {
                          TextBox t = o as TextBox;
                           u += t.Name + ": " + t.Text + Environment.NewLine;
                      }
                }
               MessageBox.Show( u );
            }
        }

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