Cod C# si XAML

MainWindow.xaml.cs

using System.Windows;

namespace SampleWpf
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void BtnInserareOnClick(object sender, RoutedEventArgs e)
        {
            var mesaj = TxtMesaj.Text;
            LstMesaje.Items.Add(mesaj);
            TbMesaj.Text = string.Format("Mesaj adaugat: {0}", mesaj);
            TxtMesaj.Text = string.Empty;
        }
    }
}

MainWindow.xaml

<Window x:Class="SampleWpf.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Prima mea aplicatie" SizeToContent="WidthAndHeight" Background="SkyBlue" >
    <StackPanel>
        <TextBlock x:Name="TbMesaj" Margin="4" />
        <ListBox x:Name="LstMesaje" Height="200" Width="300" Margin="4" />
        <StackPanel Orientation="Horizontal">
            <TextBox x:Name="TxtMesaj" Width="200" Margin="4" />
            <Button Content="Adauga mesaj" Click="BtnInserareOnClick" Margin="4" />
        </StackPanel>
    </StackPanel>
</Window>

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