How do you pass multiple enum values in C#?

Question

Sometimes when reading others\' C# code I see a method that will accept multiple enum values in a single parameter. I always thought it was kind of neat, but never looked in

Answer 1

Mark your enum with the [Flags] attribute. Also ensure that all of your values are mutually exclusive (two values can't add up to equal another) like 1,2,4,8,16,32,64 in your case

[Flags]
public enum DayOfWeek
{ 
Sunday = 1,   
Monday = 2,   
Tuesday = 4,   
Wednesday = 8,   
Thursday = 16,   
Friday = 32,    
Saturday = 64
}

When you have a method that accepts a DayOfWeek enum use the bitwise or operator (|) to use multiple members together. For example:

MyMethod(DayOfWeek.Sunday|DayOfWeek.Tuesday|DayOfWeek.Friday)

To check if the parameter contains a specific member, use the bitwise and operator (&) with the member you are checking for.

if(arg & DayOfWeek.Sunday == DayOfWeek.Sunday)
Console.WriteLine("Contains Sunday");