Getting the max value of an enum

How do you get the max value of an enum?

Enum.GetValues() seems to return the values in order, so you can do something like this:

// given this enum:
public enum Foo
{
    Fizz = 3, 
    Bar = 1,
    Bang = 2
}

// this gets Fizz
var lastFoo = Enum.GetValues(typeof(Foo)).Cast<Foo>().Last();

Edit

For those not willing to read through the comments: You can also do it this way:

var lastFoo = Enum.GetValues(typeof(Foo)).Cast<Foo>().Max();

... which will work when some of your enum values are negative.

I agree with Matt's answer. If you need just min and max int values, then you can do it as follows.

Maximum:

Enum.GetValues(typeof(Foo)).Cast<int>().Max();

Minimum:

Enum.GetValues(typeof(Foo)).Cast<int>().Min();

According to Matt Hamilton's answer, I thought on creating an Extension method for it.

Since ValueType is not accepted as a generic type parameter constraint, I didn't find a better way to restrict T to Enum but the following.

Any ideas would be really appreciated.

PS. please ignore my VB implicitness, I love using VB in this way, that's the strength of VB and that's why I love VB.

Howeva, here it is:

C#:

static void Main(string[] args)
{
    MyEnum x = GetMaxValue<MyEnum>(); //In newer versions of C# (7.3+)
    MyEnum y = GetMaxValueOld<MyEnum>();  
}

public static TEnum GetMaxValue<TEnum>()
  where TEnum : Enum
{
     return Enum.GetValues(typeof(TEnum)).Cast<TEnum>().Max();
}

//When C# version is smaller than 7.3, use this:
public static TEnum GetMaxValueOld<TEnum>()
  where TEnum : IComparable, IConvertible, IFormattable
{
    Type type = typeof(TEnum);

    if (!type.IsSubclassOf(typeof(Enum)))
        throw new
            InvalidCastException
                ("Cannot cast '" + type.FullName + "' to System.Enum.");

    return (TEnum)Enum.ToObject(type, Enum.GetValues(type).Cast<int>().Last());
}



enum MyEnum
{
    ValueOne,
    ValueTwo
}

VB:

Public Function GetMaxValue _
    (Of TEnum As {IComparable, IConvertible, IFormattable})() As TEnum

    Dim type = GetType(TEnum)

    If Not type.IsSubclassOf(GetType([Enum])) Then _
        Throw New InvalidCastException _
            ("Cannot cast '" & type.FullName & "' to System.Enum.")

    Return [Enum].ToObject(type, [Enum].GetValues(type) _
                        .Cast(Of Integer).Last)
End Function

This is slightly nitpicky but the actual maximum value of any enum is Int32.MaxValue (assuming it's a enum derived from int). It's perfectly legal to cast any Int32 value to an any enum regardless of whether or not it actually declared a member with that value.

Legal:

enum SomeEnum
{
    Fizz = 42
}

public static void SomeFunc()
{
    SomeEnum e = (SomeEnum)5;
}

Getting the max value of an enum

C#:

VB:

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