How can you enumerate an enum in C#?
E.g., the following code does not compile:
public enum Suit
{
Spades,
Hearts,
Clubs,
Diamonds
}
public void EnumerateAllSuitsDemoMethod()
{
foreach (Suit suit in Suit)
{
DoSomething(suit);
}
}
And it gives the following compile-time error:
'Suit' is a 'type' but is used like a 'variable'
It fails on the Suit keyword, the second one.
If you're using .NET 5 or newer, use this solution.
foreach (Suit suit in (Suit[]) Enum.GetValues(typeof(Suit)))
{
}
Note: The cast to (Suit[]) is not strictly necessary, but it does make the code 0.5 ns faster.
It looks to me like you really want to print out the names of each enum, rather than the values. In which case Enum.GetNames() seems to be the right approach.
public enum Suits
{
Spades,
Hearts,
Clubs,
Diamonds,
NumSuits
}
public void PrintAllSuits()
{
foreach (string name in Enum.GetNames(typeof(Suits)))
{
System.Console.WriteLine(name);
}
}
By the way, incrementing the value is not a good way to enumerate the values of an enum. You should do this instead.
I would use Enum.GetValues(typeof(Suit)) instead.
public enum Suits
{
Spades,
Hearts,
Clubs,
Diamonds,
NumSuits
}
public void PrintAllSuits()
{
foreach (var suit in Enum.GetValues(typeof(Suits)))
{
System.Console.WriteLine(suit.ToString());
}
}
Just by combining the top answers, I threw together a very simple extension:
public static class EnumExtensions
{
/// <summary>
/// Gets all items for an enum value.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="value">The value.</param>
/// <returns></returns>
public static IEnumerable<T> GetAllItems<T>(this T value) where T : Enum
{
return (T[])Enum.GetValues(typeof (T));
}
}
It is clean, simple, and, by Jeppe Stig Nielsen's comment, fast.