Get CRC checksum of an NSData in Objective-C

问题

How can I count CRC (32 or 64) of an NSData object in Objective-C?

Thanks in advance!

回答1:

Have a look here for a CRC32 for NSData

http://classroomm.com/objective-c/index.php?action=printpage;topic=2891.0

回答2:

Use crc32() function from zlib library:

#import <zlib.h>

NSData *data;

// ...

unsigned long result = crc32(0, data.bytes, data.length);
NSLog(@"CRC32: %lu", result);

Make sure to link libz library with your project:

回答3:

From iOS11 use this:

unsigned long result = crc32_z(0, data.bytes, data.length);

来源：https://stackoverflow.com/questions/4115059/get-crc-checksum-of-an-nsdata-in-objective-c