macOS swap char in NSString

[smokyonion]

Dear all:

I want to compare a NSString ( I get this NSString from [NSData description]

@"<55a1b2c3 aa>" this is supposed to be read from my serial device;

but sometimes the computer will return @"<a1b2c3aa 55>"

How do I quickly swap it as the original format @"<55a1b2c3 aa>"

I have looked up the Apple Developer Reference but it seems there is no such swapping methods.. do I miss something?

Any replies will be highly appreciated. Thank you guys.

 

[kainjow]

Don't rely on the description method for anything beyond debugging.

If you want to access the raw data of the NSData object, use the bytes or getBytes:length: methods. Once you have the data, you can cast it to another data type and use the various NSSwap* functions.

 

[smokyonion]

Guys: I found some methods and I tried to combine them to get what I want
I know...it looks a little stupid but so far it works
So is there a better way to do it?


assuming hexString is @"<a1b2c3aa 55>"
the finalString will be @"<55a1b2c3 aa>"

NSString *stepOneString = [[NSString alloc] initWithString:@"<55"];

NSString *stepTwoString = [hexString substringToIndex:9];

NSString *stepThreeString = [stepTwoString substringFromIndex:1];

NSString *stepFourString = [stepThreeString substringToIndex:6];

NSString *appendString = [stepOneString stringByAppendingString:stepFourString];

NSString *finalString = [appendString stringByAppendingString:@" aa>"];
NSLog(@"Final: %@, length: %i",finalString, [finalString length]);

kainjow, thank you so much for your reply,

I'll look up the NSData reference and NSSwap try to figure it out. I'll keep this posted when I understand how to use it.

 

[Mac Player]

Use the mutable classes, NSMutableString or NSMutableData.

 

[smokyonion]

Use the mutable classes, NSMutableString or NSMutableData.

Hello, Mac Player:

Thank you for your reply, I have checked the NSMutableString, it looks like

a nice way to solve my problem. Thank you so much. I really enjoy learning things from you guys. You rock~


a Mac Programming newbie