16进制string转NSData

// hex string转 data

- (NSData *)dataFromHexString:(NSString *)string

{

string = [string lowercaseString];

NSMutableData *data= [NSMutableData new];

unsigned char whole_byte;

char byte_chars[3] = {'\0','\0','\0'};

int i = 0;

int length = string.length;

while (i < length-1) {

char c = [string characterAtIndex:i++];

if (c < '0' || (c > '9' && c < 'a') || c > 'f')

continue;

byte_chars[0] = c;

byte_chars[1] = [string characterAtIndex:i++];

whole_byte = strtol(byte_chars, NULL, 16);

[data appendBytes:&whole_byte length:1];

}

return data;

}

Usage

======

NSData *data = [self dataFromHexString:@"544A160826214510"];

NSLog(@"%@", data);