C# Enum Flags Comparison

Question

Given the following flags,

  [Flags]
    public enum Operations
    {
        add = 1,
        subtract = 2,
        multiply = 4,
        divide = 8,
        ev         


        

Answer 1

Change your inner & to |:

if ((operation & (Operations.add | Operations.eval)) == (Operations.add | Operations.eval))

This is equivalent to:

if( ((operation & Operations.add)==Operations.add) &&
    ((operation & Operations.eval)==Operations.eval))

which might be more readable. You might also want to consider an Extension like this:

public static bool HasFlag(this Operations op, Operations checkflag)
{
    return (op & checkflag)==checkflag;
}

then you can do this:

if(operation.HasFlag(Operations.add) && Operations.HasFlag(Operations.eval))

which might be even more readable. Finally you could create this extension for even more fun:

public static bool HasAllFlags(this Operations op, params Operations[] checkflags)
{
    foreach(Operations checkflag in checkflags)
    {
        if((op & checkflag)!=checkflag)
            return false;
    }
    return true;
}

Then your expression could turn into:

if(operation.HasAllFlags(Operations.add, Operations.eval))