Use Dictionary to record which textbox has been changed and not saved : TextBox « Windows Presentation Foundation « VB.Net

1. VB.Net
2. Windows Presentation Foundation
3. TextBox

Use Dictionary to record which textbox has been changed and not saved

     
<Window x:Class="Commands.TwoDocument"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="TwoDocument" Height="300" Width="300">

  <Window.Resources>
    <CommandBinding x:Key="binding" Command="ApplicationCommands.Save" Executed="SaveCommand" CanExecute="SaveCommand_CanExecute" />
  </Window.Resources>

  <Grid>
    <Grid.RowDefinitions>
      <RowDefinition Height="Auto"></RowDefinition>
      <RowDefinition Height="Auto"></RowDefinition>
      <RowDefinition></RowDefinition>
      <RowDefinition></RowDefinition>
    </Grid.RowDefinitions>
    <Menu Grid.Row="0">
      <MenuItem Header="File">
        <MenuItem Command="New"></MenuItem>
        <MenuItem Command="Open"></MenuItem>
        <MenuItem Command="Save"></MenuItem>
        <MenuItem Command="SaveAs"></MenuItem>
        <Separator></Separator>
        <MenuItem Command="Close"></MenuItem>
      </MenuItem>
    </Menu>

    <TextBox Margin="5" Grid.Row="2" TextWrapping="Wrap" AcceptsReturn="True" TextChanged="txt_TextChanged">
      <TextBox.CommandBindings>
        <StaticResource ResourceKey="binding"></StaticResource>
      </TextBox.CommandBindings>
      
    </TextBox>

  </Grid>
</Window>
//File:Window.xaml.vb
Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Data
Imports System.Windows.Documents
Imports System.Windows.Input
Imports System.Windows.Media
Imports System.Windows.Media.Imaging
Imports System.Windows.Shapes

Namespace Commands
  Public Partial Class TwoDocument
    Inherits System.Windows.Window
    Private isDirty As New Dictionary(Of [Object], Boolean)()
    Public Sub New()
      InitializeComponent()
    End Sub

    Private Sub SaveCommand(sender As Object, e As ExecutedRoutedEventArgs)
      Dim text As String = DirectCast(sender, TextBox).Text
      isDirty(sender) = False
    End Sub
    Private Sub txt_TextChanged(sender As Object, e As RoutedEventArgs)
      isDirty(sender) = True
    End Sub
    Private Sub SaveCommand_CanExecute(sender As Object, e As CanExecuteRoutedEventArgs)
      If isDirty.ContainsKey(sender) AndAlso isDirty(sender) = True Then
        e.CanExecute = True
      Else
        e.CanExecute = False
      End If
    End Sub
  End Class
End Namespace

   
    
    
    
    
  

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