C# wait for user to finish typing in a Text Box

Question

Is there a way in C# to wait till the user finished typing in a textbox before taking in values they have typed without hitting enter?

Revised this question a little

Answer 1

I define "finished typing" now as "user has typed something but has not typed anything after a certain time". Having that as a definition i wrote a little class that derives from TextBox to extend it by a DelayedTextChanged event. I do not ensure that is complete and bug free but it satisfied a small smoke test. Feel free to change and/or use it. I called it MyTextBox cause i could not come up with a better name right now. You may use the DelayedTextChangedTimeout property to change the wait timeout. Default is 10000ms (= 10 seconds).

public class MyTextBox : TextBox
{
    private Timer m_delayedTextChangedTimer;

    public event EventHandler DelayedTextChanged;

    public MyTextBox() : base() 
    {
        this.DelayedTextChangedTimeout = 10 * 1000; // 10 seconds
    }

    protected override void Dispose(bool disposing)
    {
        if (m_delayedTextChangedTimer != null)
        {
            m_delayedTextChangedTimer.Stop();
            if (disposing)
                m_delayedTextChangedTimer.Dispose();
        }

        base.Dispose(disposing);            
    }

    public int DelayedTextChangedTimeout { get; set; }

    protected virtual void OnDelayedTextChanged(EventArgs e)
    {
        if (this.DelayedTextChanged != null)
            this.DelayedTextChanged(this, e);
    }

    protected override void OnTextChanged(EventArgs e)
    {
        this.InitializeDelayedTextChangedEvent();
        base.OnTextChanged(e);            
    }                

    private void InitializeDelayedTextChangedEvent()
    {
        if (m_delayedTextChangedTimer != null)
            m_delayedTextChangedTimer.Stop();

        if (m_delayedTextChangedTimer == null || m_delayedTextChangedTimer.Interval != this.DelayedTextChangedTimeout)
        {                
            m_delayedTextChangedTimer = new Timer();
            m_delayedTextChangedTimer.Tick += new EventHandler(HandleDelayedTextChangedTimerTick);
            m_delayedTextChangedTimer.Interval = this.DelayedTextChangedTimeout;
        }

        m_delayedTextChangedTimer.Start();
    }

    private void HandleDelayedTextChangedTimerTick(object sender, EventArgs e)
    {
        Timer timer = sender as Timer;
        timer.Stop();

        this.OnDelayedTextChanged(EventArgs.Empty);
    }
}