Help using flags

[Bob Harrison]

I am monitoring some electronic equipment. Every few seconds i poll for
equipment status. The results are returned in 6 groups - like 0A 40 08 00 00
00. Currently only the first 3 bytes contain meaningful info

each bit reports either normal operation (a 0) or an error condition (a 1)
for a component of the equipment.

I set up <flag> Enum for each byte (just the first 3 bytes for now)
Enum Byte1
None=0
component1=1
component2 =2
component3 = 4
.... to 128
end enum

Enum Byte2
None=0
component1=1
component2 =2
component3 = 4
.... to 128
end enum

i need a routine that will quickly anaylyze and let me test the status of
each flag.

Thanks.

[Kevin Spencer]

Hi Bob,

You can use an Enumeration to check flags, but the values of the
enumerations must match the values of the flags. Flags are stored as bits,
that is binary values:

1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, etc.

If you give these values to your enumerations, you can use Bitwise operators
to check them.

The following is an article about VB.Net enumerations, including Flags
enumerations:

http://aspnet.4guysfromrolla.com/articles/042804-1.aspx

For more information on VB.Net bitwise operators, see:

http://msdn.microsoft.com/library/de...ml/vaopror.asp
http://msdn.microsoft.com/library/de...dxbitshift.asp
http://msdn.microsoft.com/library/de...fficiently.asp

--
HTH,

Kevin Spencer
Microsoft MVP
..Net Developer
Who is Mighty Abbott?
A twin turret scalawag.

"Bob Harrison" <Bo*********@discussions.microsoft.com> wrote in message
news:36**********************************@microsof t.com...

I am monitoring some electronic equipment. Every few seconds i poll for
equipment status. The results are returned in 6 groups - like 0A 40 08 00
00
00. Currently only the first 3 bytes contain meaningful info

each bit reports either normal operation (a 0) or an error condition (a 1)
for a component of the equipment.

I set up <flag> Enum for each byte (just the first 3 bytes for now)
Enum Byte1
None=0
component1=1
component2 =2
component3 = 4
... to 128
end enum

Enum Byte2
None=0
component1=1
component2 =2
component3 = 4
... to 128
end enum

i need a routine that will quickly anaylyze and let me test the status of
each flag.

Thanks.

[Chris Dunaway]

I suggest taking a look at the BitArray class. It will take an integer
or array of bytes in its constructor. You can then test the status in
individual bits.

[Bob Harrison]

I ended up returning the bytes and doing a routine like this

dim rslt as integer
For ii as integer = 0 to 2
Select case ii
case 0
result= byte(ii) and equipment.flagbyte0.test1 '(test one is
value=1)
if result=equipment.flgbyte0.test1 then
doAlarmIcon
else
donormalicon
end if

....code for flags 2,4,8,16,32,64,128
Case 1 'for net status byte
......

"Chris Dunaway" wrote:

I suggest taking a look at the BitArray class. It will take an integer
or array of bytes in its constructor. You can then test the status in
individual bits.