Avoiding disposing system-defined Pen and Brush instances

Question

I understand it is best practise to call Dispose() on instances of Pen and Brush, except if they\'ve been set to the system-predefined values (eg. System.Drawing.Brushes, Syste

Answer 1

Just for completeness, using Reflector I see that the System.Drawing.Pen and System.Drawing.SolidBrush classes have a private field named 'immutable'.

This field appears to be set to true when the object refers to a system-defined resource, so you could use reflection to carefully check the value of this field to decide whether to call Dispose() on it.