WPF: simple TextBox data binding

Question

I have this class:

public partial class Window1 : Window {     public String Name2;      public Window1()     {         InitializeComponent();         Name2 = new String('a', 5);         myGrid.DataContext = this;     }      // ... } 

And I want to display the string Name2 in the textbox.

<Grid Name="myGrid" Height="437.274">   <TextBox Text="{Binding Path=Name2}"/> </Grid> 

But the string isn't displayed. Also, if the string Name2 is updated periodically using a TimerCallback, do I need to do anything to make sure the textbox is updated when the data changes?

Answer 1

Name2 is a field. WPF binds only to properties. Change it to:

public string Name2 { get; set; } 

Be warned that with this minimal implementation, your TextBox won't respond to programmatic changes to Name2. So for your timer update scenario, you'll need to implement INotifyPropertyChanged:

partial class Window1 : Window, INotifyPropertyChanged {   public event PropertyChangedEventHandler PropertyChanged;    protected void OnPropertyChanged(string propertyName)   {         PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));   }    private string _name2;    public string Name2   {     get { return _name2; }     set     {       if (value != _name2)       {          _name2 = value;          OnPropertyChanged("Name2");       }     }   } } 

You should consider moving this to a separate data object rather than on your Window class.