The following seems to be a relatively common pattern (to me, not to the community at large) to bind a string variable to the contents of a TextBox.

class MyBackEndClass
{
    public event EventHandler DataChanged;
    string _Data;
    public string Data
    {
        get { return _Data; }
        set
        {
            _Data = value;
            //Fire the DataChanged event
        }
    }
}

class SomeForm : // Form stuff
{
    MyBackEndClass mbe;
    TextBox someTextBox;
    SomeForm() 
    {
        someTextBox.TextChanged += HandleTextBox();
        mbe.DataChanged += HandleData();
    }

    void HandleTextBox(Object sender, EventArgs e)
    {
        mbe.Data = ((TextBox)sender).Text;
    }

    void HandleData(Object sender, EventArgs e)
    {
        someTextBox.Text = ((MyBackEndClass) sender).Data;
    }
}

The problem is that changing the TextBox fires the changes the data value in the backend, which causes the textbox to change, etc. That runs forever.

Is there a better design pattern (other than resorting to a nasty boolean flag) that handles this case correctly?

EDIT: To be clear, in the real design the backend class is used to synchronize changes between multiple forms. Therefore I can't just use the SomeTextBox.Text property directly.

Billy3