How to convert HEX to NSString in Objective-C?

Question

I have a NSString with hex string like \"68656C6C6F\" which means \"hello\".

Now I want to convert the hex string into another NSString object which shows \"hello\"

Answer 1

This should do it:

- (NSString *)stringFromHexString:(NSString *)hexString {

    // The hex codes should all be two characters.
    if (([hexString length] % 2) != 0)
        return nil;

    NSMutableString *string = [NSMutableString string];

    for (NSInteger i = 0; i < [hexString length]; i += 2) {

        NSString *hex = [hexString substringWithRange:NSMakeRange(i, 2)];
        NSInteger decimalValue = 0;
        sscanf([hex UTF8String], "%x", &decimalValue);
        [string appendFormat:@"%c", decimalValue];
    }

    return string;
}