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Objective-C

ARC4 PRNG (Pseudo Random Number Generator)

See more Encryption Examples

Uses the ARC4 stream encryption algorithm as a pseudo random number generator.

Chilkat Objective-C Downloads

Objective-C
#import <CkoCrypt2.h>
#import <NSString.h>

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

CkoCrypt2 *crypt = [[CkoCrypt2 alloc] init];

// Set the encryption algorithm to ARC4:	
crypt.CryptAlgorithm = @"arc4";

// We want the encrypted output to be a hex-encoded string.
crypt.EncodingMode = @"hex";

NSString *key = @"000102030405060708090A0B0C0D0E0F";
NSString *data = @"12345678";

// Key length is 128 bits in this example.
crypt.KeyLength = [NSNumber numberWithInt:128];
[crypt SetEncodedKey: key encoding: @"hex"];

// Generate 16 "random" 8-byte blocks, encoded as hex strings.
// This example will generate the identical output each time
// it is run.
NSString *cipherHex = 0;
int i;
for (i = 0; i <= 15; i++) {
    cipherHex = [crypt EncryptStringENC: data];
    NSLog(@"%@",data);
    NSLog(@"%@",cipherHex);
    data = cipherHex;
}