c# - how to retrieve back values from an ORed flag -



c# - how to retrieve back values from an ORed flag -

assume im dealing createfilea

i have

public const generic_all int32 = &h10000000 public const generic_read int32 = &h80000000 public const generic_write int32 = &h40000000 public const generic_execute int32 = &h20000000

thus means if need read , write do

generic_read | generic_write = 0c0000000h

how api reverse or operation know flags contains ?, in words assume got value "0c0000000h" , need know accesses contains, operations should on number ?

my point if have 100 flags , ored/anded them sick end complicated number, how retrieve flags used compose number ?

the binary , operation can used test individual bits (aka flags).

for instance

bool b = (value & generic_read) != 0;

evaluates true if generic_read ored value previously, regardless of other flags have been combined.

if doesn't explain enough, perhaps http://en.wikipedia.org/wiki/bitwise_operation#and help.

c# c++ c bitflags

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