Hello anh Long,

Em đang học WPF tới bài Binding, mà em code chạy đc mà nó chạy sai.

Nhập chữ vào txbSource, chữ hiện ra ở ô  txbBlinding. Nhưng build xong thì nó như hình:

[img]http://sv1.upsieutoc.com/2017/05/31/Capture17648.png[/img]

<Window x:Class="WpfApp1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp1"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <TextBlock x:Name="txbSource" VerticalAlignment="Top"></TextBlock>
        <TextBlock x:Name="txbBinding" VerticalAlignment="Center"></TextBlock>
        <Button x:Name="btnBinding" VerticalAlignment="Bottom" Content="Binding" Click="btnBinding_Click"></Button>
    </Grid>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp1
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void btnBinding_Click(object sender, RoutedEventArgs e)
        {
            txbBinding.Text = txbSource.Text;
        }
    }
}