Convert NSString to unsigned char type array in objective C

Question

I want to convert NSString to unsigned char type array, I have searched many things but have not found a way to do it, can someone suggest me? ex: input : 16 output: 0x01, 0x06

The input has only the characters of hexa code. I am newly for this objective C and cocoa application so please help on this. Thanks!

sorry for not write clearly, I want use hexa code, input only number and "A,B,C,D,E,F". A = 0x10, B =0x11... — KiDo Ruan, Jul 12 '20 at 09:25
Hex are two bytes. Do you mean this: https://stackoverflow.com/questions/2501033/nsstring-hex-to-bytes — vadian, Jul 12 '20 at 14:45
Welcome to SO. Please add a [example] to your question. See also [ask]. — koen, Jul 12 '20 at 16:25
@vadian yes, It seems that is what I was looking for, thank you! — KiDo Ruan, Jul 13 '20 at 01:47

score 0 · Answer 1 · answered Jul 15 '20 at 07:10

0

const char* array = [string UTF8String];

This will give you a pointer to the null-terminated array with UTF8 representation of the string.

answered Jul 15 '20 at 07:10

Davyd Geyl

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score -1 · Answer 2 · answered Jul 12 '20 at 09:51

-1

Loop the characters in the string and then you can do what you want with them, e.g. print or calc or whatever. I'm sure there are samples of this lying around.

// s is the string ...
for ( NSUInteger i = 0; i < s.length; i ++ )
{
  unichar c = [s characterAtIndex:i];

  // ... do something with c
}

answered Jul 12 '20 at 09:51

skaak

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Well ... this approach is overkill for converting to hex but made sense earlier. – skaak Jul 13 '20 at 09:19

Convert NSString to unsigned char type array in objective C

2 Answers2