问题
Possible Duplicate:
how to get bit by bit data from a integer value in c?
I have a 8-bit byte and I want to get a bit from this byte, like getByte(0b01001100, 3) = 1
回答1:
Firstoff, 0b prefix is not C but a GCC extension of C.
To get the value of the bit 3 of an uint8_t a, you can use this expression:
((a >> 3) & 0x01)
which would be evaluated to 1 if bit 3 is set and 0 if bit 3 is not set.
回答2:
First of all C 0b01... doesn't have binary constants, try using hexadecimal ones. Second:
uint8_t byte;
printf("%d\n", byte & (1 << 2);
回答3:
Use the & operator to mask to the bit you want and then shift it using >> as you like.
来源：https://stackoverflow.com/questions/8695945/c-get-a-bit-from-a-byte