CRC32 - Fastest Implementation Available VB6

[wqweto]

But I'm a bit curious what kind of software needs to calculate CRC32s much anyway, or for that matter needs to checksum so much data that a straight VB6 function isn't fast enough.

Actually recently refactored an unzipping class and noticed that calculating CRC32 reduced speed a lot (probably in half). That's when I decided to skip it altogether with a conditional compilation option.

Unfortunately OP code is too bloated to be easily plugged in my skinny class. I doubt that he can beat a for cycle and a XOR for brevity

For lIdx = 0 To lSize - 1
    lOutputCrc32 = (((lOutputCrc32 And &HFFFFFF00) \ &H100) And &HFFFFFF) Xor (m_lCrc32Table((lOutputCrc32 And &HFF) Xor uCtx.baInStream(lOffset + lIdx)))
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cheers,
</wqw>