oc 16进制字符串转NSstring,NSNumber

- (NSNumber *)hexToNumber:(NSString *)hexStr{
    if(hexStr == nil){
        return nil;
    }
    NSScanner *scanner = [NSScanner scannerWithString:hexStr];
    unsigned long long value;
    [scanner scanHexLongLong:&value];
    
    NSNumber *hexNumber = [NSNumber numberWithLongLong:value];
    return hexNumber;
    
}