Enums and Bit Fields [Resolved]

[Ideas Man]

When you use bit fields with enumerated data types, you can use the elements in the Enum as flags. Now I know that you have to add the <Flags()> attribute to an Enum to turn this behaviour on, and there's no problems there, however, how do you find out the combination of values that has been set?

For example:

<Flags()> _
Enum myButtons
    [Next] = 1
    Back = 2
    Cancel = 4
    '...
End Enum
 
Public Sub ShowButtons(buttons as myButtons)
    '...?
End Sub
 
'...
'Some other sub
Call ShowButtons(myButtons.Next Or myButtons.Back)

How do you get which buttons were passed so you can work on them?

[wossname]

Use the AND operator. the OR is used to set bits not query them.

If (Data AND myButtons.Back) > 0 then 'back pressed

[Ideas Man]

You legend, thanks heaps for that. I knew it would have to be something simple, pity it's not easily visible in the MSDN documentation or with a Google search.

[wossname]

Well its nothing more than elementary binary arithmatic, its the normal way to check flags on most languages / platforms. Its worth swotting up on Binary ops anyway.

AND OR NOT XOR... also Bit Masks and shifting.

[Ideas Man]

Well, all of that is news to me. I know none of that, lol.