bit manipulation - How do I store a byte into a 4 byte number without changing the bytes around it? -

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so if have 4 byte number (say hex) , want store byte dd hex, @ nth byte position without changing other elements of hex's number, what's easiest way of going that? i'm guessing it's combination of bitwise operations, i'm still quite new them, , have found them quite confusing far?

byte n = 0xdd; uint = 0x12345678; = (i & ~0x0000ff00) | ((uint)n << 8);

edit: forgot mention, careful if you're doing signed data types, things don't inadvertently sign-extended.


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