iOS 转成16进制

- (NSString *)hexStringFromString:(NSString *)string{    NSData *myD = [string dataUsingEncoding:NSUTF8StringEncoding];    Byte *bytes = (Byte *)[myD bytes];    //下面是Byte 转换为16进制。    NSString *hexStr=@"";    for(int i=0;i<[myD length];i++)            {        NSString *newHexStr = [NSString stringWithFormat:@"%x",bytes[i]&0xff];///16进制数                if([newHexStr length]==1)                        hexStr = [NSString stringWithFormat:@"%@0%@",hexStr,newHexStr];                else                        hexStr = [NSString stringWithFormat:@"%@%@",hexStr,newHexStr];     }     return hexStr; }

OK