Custom Data Types

Question

Hello, quick question:

I'd like to create some custom data types, but I don't think I'm asking the right question(s).

There are "compound Boolean" values used throughout .NET, and I want to design some of my own. I've been using a series of Boolean variables, which works, but just isn't the same.

Examples from .NET include: Color.Black Alignment.Centered [fontProperties].Bold* *I forget the actual name, but you get the idea

I want to make something like this:

ColorSortQualities

• None
• DistinguishColor
• DistinguishNumberOfColors
• DistinguishColorPattern

Once that's been declared, I could do this: if(searchOptions.ColorSortQualities == DistinguishColor) [do stuff]

What is this called?

Thanks!

Answer 1

I think you want a enumeration with the [Flags] attribute.

[Flags]
enum ColorSortQualities
{
    None = 0x0,
    DistinguishColor = 0x1,
    DistinguishNumberOfColors = 0x2,
    DistinguishColorPattern = 0x4
}

This will let the caller specify any combination of those, each of which will be implemented as a bit flag. Note that this will allow 32 options, because int is a 32-bit quantity.

Your condition code would look like:

if((searchOptions & ColorSortQualities.DistinguishColor) == ColorSortQualities.DistinguishColor)

If that isn't what you mean by "series of Boolean variables", please clarify.

Answer 2

Use an enum:

  enum ColorSortQualities
  {
       None,
       DistinguishColor,
       DistinguishNumberOfColors,
       DistinguishColorPattern
  };

Answer 3

It's called an enumeration and in C# you use the keyword enum.