Objective C : Separate words in a string and join again

Question

I have a string say @"DidNotTurnUp". I want to write a function which will take this string as an input and should output @"Did Not Turn Up". What would be the best way to do this? How to separate the words in a string based on capital letters? Help appreciated.

Separating: http://stackoverflow.com/a/5806879/876283, Joining: http://stackoverflow.com/a/12156814/876283 — iNoob, Apr 24 '14 at 06:04
Look for capital letters in the string and insert space before every capital letter…hope this the logic you are looking for.. — bachman, Apr 24 '14 at 06:04
You can use the regular expression for the same. Go through this link http://stackoverflow.com/questions/7322498/insert-or-split-string-at-uppercase-letters-objective-c — user2071152, Apr 24 '14 at 06:06
@DarshanKunjadiya Please stop doing this. Your answer is pretty much visible. Reported as _not constructive_ — Desdenova, Apr 24 '14 at 06:25
What is this today?? Three people just copying the accepted answer of the linked-to question without any attribution. — Martin R, Apr 24 '14 at 06:30

nielsbot · Answer 1 · 2014-04-24T06:33:48.320

3

Here's a category on NSString that will do what you want.

@implementation NSString (SeparateCapitalizedWords)

-(NSString*)stringBySeparatingCapitalizedWords
{
    static NSRegularExpression * __regex ;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        NSError * error = nil ;
        __regex = [ NSRegularExpression regularExpressionWithPattern:@"[\\p{Uppercase Letter}]" options:0 error:&error ] ;
        if ( error ) { @throw error ; }
    });

    NSString * result = [ __regex stringByReplacingMatchesInString:self options:0 range:(NSRange){ 1, self.length - 1 } withTemplate:@" $0" ] ;
    return result ;
}

@end

edited Apr 24 '14 at 06:33

answered Apr 24 '14 at 06:10

nielsbot

15,922
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1

This gives the result " id ot urn p". – Martin R Apr 24 '14 at 06:12
you're right! I fixed it. – nielsbot Apr 24 '14 at 06:34
I think the other regex might be better: any lower case letter followed by an uppercase one... but I would prefer this code structure in production. Depends how often you will be calling it. – nielsbot Apr 24 '14 at 06:43
1

+1 for using `\p{Uppercase Letter}` which should also cover non-ASCII uppercase letters such as Ä, Ǣ, Я. – Martin R Apr 25 '14 at 06:06
Ok... I think this regex works better than (a-z)(A-Z), since this one will handle "IAmNewHere" --> "I Am New Here" for example. – nielsbot Apr 25 '14 at 06:43
`result` ends up containing the initial word uncapitalized. So if you're trying to generate a display name from, say, an obj-c property name such as `myValue`, you end up with lowercase `my`. `return [result capitalizedString]` fixes this, with final output as "My Value". – Martin-Gilles Lavoie Jul 04 '18 at 05:54

Darshan Kunjadiya · Answer 2 · 2014-04-25T06:18:08.573

1

Try this

NSString *YourString=@"YouAreAGoodBoy";
NSString *outString;
NSString *string=@"";
NSUInteger length = [YourString length];
for (NSUInteger i = 0; i < length; i++)
{
    char c = [YourString characterAtIndex:i];
    if (i > 0 && c >= 65 && c <=90)
    {
        outString=[NSString stringWithFormat:@"%C", c];
        string = [NSString stringWithFormat:@"%@%@%@",string,@" ",outString];
    }
    else
    {
        outString=[NSString stringWithFormat:@"%C", c];
        string = [NSString stringWithFormat:@"%@%@",string,outString];

    }
}

NSLog(@"%@",string);

Hope this code is useful for you .

edited Apr 25 '14 at 06:18

answered Apr 24 '14 at 06:22

Darshan Kunjadiya

3,323
1
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I love this answer, it's original. One side note deserves mention though; in ASCII chars between 65 & 90 represent the uppercase letters hence the `if` condition. – Desdenova Apr 24 '14 at 07:05
"%c" works only with ASCII characters. You should use at least "%C" to make it work with UTF-16 characters (ä, €, ...). And there are uppercase letters which are not in the ASCII range such as Ä, Ǣ, Я. – Martin R Apr 25 '14 at 06:09

score 0 · Answer 3 · edited May 23 '17 at 10:26

NSString *string = @"ThisStringIsJoined";
NSRegularExpression *regexp = [NSRegularExpression 
    regularExpressionWithPattern:@"([a-z])([A-Z])" 
    options:0 
    error:NULL];
NSString *newString = [regexp 
    stringByReplacingMatchesInString:string 
    options:0 
    range:NSMakeRange(0, string.length) 
    withTemplate:@"$1 $2"];
NSLog(@"Changed '%@' -> '%@'", string, newString);

Copied from https://stackoverflow.com/a/7322720/2842382, try this

Objective C : Separate words in a string and join again

3 Answers3