Question

Is it usable or this doesn’t work: to change the Text Box.Text and the property behind to change can a binding of this type be made(i know that this can be made with an event from Text Box, i am looking for some kind of binding that can be made) ?
Should i just use Text Box.Text in my cod?

<TextBox Text="{Binding Path=NumeClient, Mode=TwoWay}" Height="23" HorizontalAlignment="Left" Margin="117,21,0,0" Name="textBox1" VerticalAlignment="Top" Width="249" />

public string NumeClient { get; set; }

Answer 1

This Makes both your property changes the TextBox and the TextBox changes the property (from MSDN)

Add in your class contructor DataContext = this;

 public class Person : INotifyPropertyChanged
      {
          private string name;
          // Declare the event
          public event PropertyChangedEventHandler PropertyChanged;
          public string PersonName
          {
              get { return name; }
              set
              {
                  name = value;
                  // Call OnPropertyChanged whenever the property is updated
                  OnPropertyChanged("PersonName");
              }
          }

          // Create the OnPropertyChanged method to raise the event
          protected void OnPropertyChanged(string name)
          {
              PropertyChangedEventHandler handler = PropertyChanged;
              if (handler != null)
              {
                  handler(this, new PropertyChangedEventArgs(name));
              }
          }
      }

XAML :

<TextBox Text="{Binding Path=PersonName, Mode=TwoWay}" />

Hope it helps