C#

<br />
        private void textBox1_Validating(object sender, CancelEventArgs e)<br />
        {<br />
            if (string.Compare(textBox1.Text, "foo") != 0)<br />
            {<br />
                e.Cancel = true;<br />
            }<br />
<br />
        }<br />
<br />
        private void button1_Click(object sender, EventArgs e)<br />
        {<br />
            MessageBox.Show("bar!");<br />
        }<br />

private String myField = String.Empty;
 
// Properties have get/set accessors...
public String MyProperty {
    get {
        return this.myField;
    }
}

;  /// <summary>
  /// Create a temporary file. The file will be removed as soon as 
  /// the instance of this class is disposed.
  /// </summary>
  public class TempFile : IDisposable
  {
    private string _fileName;
    private bool disposed = false;
    /// <summary>
    /// Instantiate a new instance of <see cref="TempFile"/>.
    /// </summary>
    public TempFile()
    {
      _fileName = Path.GetTempFileName();
    }

    /// <summary>
    /// Get the temporary file name.
    /// </summary>
    public string FileName
    {
      get { return _fileName; }
    }

    #region IDisposable Members
    /// <summary>
    /// Dispose of the temporary file.
    /// </summary>
    public void Dispose()
    {
      Dispose(true);
    }
    protected void Dispose(bool dispose)
    {
      if (dispose && !disposed)
      {
        if (File.Exists(_fileName))
        {
          try
          {
            File.Delete(_fileName);
          }
          catch (IOException ex)
          {
            Trace.WriteLine(string.Format("Unable to remove temporary file because of {0}", 
              ex.Message));
          }
        }
        disposed = true;
        GC.SuppressFinalize(this);
      }
    }
    #endregion
  }