extract each byte from an integer varialbe

[peter ho]

Hi! I hope someone can help me on this. Is there a way to extract each byte from an integer variable in C++ (4 bytes) ? thanks, peter.

[dabs]

There are lots of ways to do this: union ByteToInt { unsigned int i; struct bytes { unsigned char a; unsigned char b; unsigned char c; unsigned char d; } bytes; }; ByteToInt b2i; b2i.i = 0xFF00FF00; cout << b2i.bytes.a << endl; // etc. - not syntaxchecked or even compileable :-) but I hope you get the picture. Another method: unsigned int i = 0xFF00FFcc; unsigned char b1 = static_cast< unsigned char >( i ); unsigned char b2 = static_cast< unsigned char >( i >> 8 ); unsigned char b3 = static_cast< unsigned char >( i >> 16 ); unsigned char b4 = static_cast< unsigned char >( i >> 24 );

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Wenn ist das Nunstück git und Slotermeyer? Ja! Beierhund das oder die Flipperwaldt gersput!

[Paul M Watt]

Basically strip off the other bytes with a mask, then shift the value to fit into a BYTE. int value; BYTE b1 = (value & 0x000000FF); BYTE b2 = (value & 0x0000FF00) >> 8; BYTE b3 = (value & 0x00FF0000) >> 16; BYTE b4 = (value & 0xFF000000) >> 24;

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Build a man a fire, and he will be warm for a day
Light a man on fire, and he will be warm for the rest of his life!

[Rick York]

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The Ten Commandments For C Programmers

[James R Twine]

Perhaps the standard macros HIWORD, LOWORD, HIBYTE and LOBYTE, so you do not reinvent the wheel?    Peace! -=- James (Sonork:100.21837) "There is nothing worse than being oblivious to the fact that you do not know what you are doing." [Get Check Favorites 1.5 Now!]