Question

I have this:

NSString *string1 = ...;
NSString *string2 = ...;

NSMutableArray *array = [NSMutableArray alloc]inithWithObjects:string1, string2]autorelease];

How do I calculate the MD5 hash (or other more appropriate hash) for each content of the array, for further comparisons?

Thanks!

Answer 1

You can use this method on every string of your array:

- (NSString*)md5HexDigest:(NSString*)input {
const char* str = [input UTF8String];
unsigned char result[CC_MD5_DIGEST_LENGTH];
CC_MD5(str, strlen(str), result);

NSMutableString *ret = [NSMutableString stringWithCapacity:CC_MD5_DIGEST_LENGTH*2];
for(int i = 0; i<CC_MD5_DIGEST_LENGTH; i++) {
    [ret appendFormat:@"%02x",result[i]];
}
return ret;
}

Do not forget to include:

#import <CommonCrypto/CommonDigest.h>