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c#enumscomparisonenum-flags

Comparing flags with flags - check for matches

Say I have an enum:

[Flags]
public enum Alpha
{
    NULL = 0,
    A0 = 1,
    A1 = 2,
    A2 = 4,
    A3 = 8
}

And I have the following:

Alpha selected = A0 | A1 | A2

Alpha compare = A1 | A3

I want to check if any of the selected flags are also in the compare flags.

The only way I can think to do this so far is (pseudocode)

foreach(Alpha flag in Enum.GetValues(typeof(Alpha)))
{
    if (selected.HasFlag(flag) && compare.HasFlag(flag))
    {
        return true
    }
}
return false

Is there a more logic-al way to do this?

Solution

  • Because it is treated as bit field, you can use it in the same fashion.

    FlagsAttribute Class

    Indicates that an enumeration can be treated as a bit field; that is, a set of flags

    bool result = (selected & compare) > 0; // First solution
bool result2 = (selected & compare).Any(); // Second solution