Should I dispose of the old font when changing the font of a control?

Question

C#, Windows Forms app.

We're re-skinning our application and I'm also changing the awful default font we used in the old one. So I thought I'd call the following function to change the font of all controls on a form when the form is loaded.

  internal static void SetFonts(Control control)
  {
    Font oldFont = control.Font;
    if (oldFont.Name != GlobalFontName)
    {
      string familyName = GlobalFontName;
      Font newFont = new System.Drawing.Font(familyName,
        oldFont.Size, oldFont.Style, GraphicsUnit.Point, 0);
      control.Font = newFont;
      //oldFont.Dispose();
    }
    foreach (Control child in control.Controls)
      SetFonts(child);
  }

I thought it would keep resources down if I disposed of the old font after reassigning the control with the new one, but on closing the form I'm receiving access violation exceptions from one control type from a set of third party controls. If I comment out the line "oldFont.Dispose()" then I don't get the exception.

Is this a bug of the third party control set or is this to be expected?
Memory wise, can I get away with not explicitly disposing of the old font (The app runs on kiosks for 12hr+ a day) ?

Answer 1

Don't dispose of the old Font, that's the job of the Control whose font you're changing. Also, use tools such as GDIView to monitor your handles (such as fonts).