using statement for multiple assignments to the variable

Question

I have a variable "pen" of type System.Drawing.Pen which is getting assigned multiple times in a particular method. I want to put it within "using" statement. How I can do that?

Pen pen = new Pen(Color.Gray);
// some code which uses gray value
pen = new Pen(Color.Green);
// some code which uses green value
pen = new Pen(Color.Red);
// some code which uses red value

Thanks in advance.

Answer 1

Well, Pen implements IDisposable since it allocates unmanaged resources (HPEN) and thus in general case using is required. In your current code you have resource leakage:

Pen pen = new Pen(Color.Gray);

// some code which uses gray value

pen = new Pen(Color.Green); // <- from now on Pen(Color.Gray) is leaked

// some code which uses green value
pen = new Pen(Color.Red);  // <- from now on Pen(Color.Green) is leaked
// some code which uses red value

You can either use predefined pens (no using required):

Pen pen = Pens.Gray;

// some code which uses gray value

pen = Pens.Green;

// some code which uses green value

pen = Pens.Red;

// some code which uses red value

Or if you want to create Pens manually, wrap them into using:

using (Pen pen = new Pen(Color.Gray)) {
  // some code which uses gray value
}

using (Pen pen = new Pen(Color.Green) {
  // some code which uses green value
}

using (Pen pen = new Pen(Color.Red)) {
  // some code which uses red value
}