Question

i would like to remove the last line from my string.. the nsstring object here is _text. My thoughts are to scan characters from the end and if i found a carriage return symbol i substring to that index, and finnish. But i don’t want to remove every carriage return, just the last one.

So i would like to do something like this:

for (int i = [_text length] ; i>0; i--) {
    char character = [_text characterAtIndex:i];
    if (character == @"\n") {
       _text = [_text substringToIndex:i];
     return;
    }
}

Any help would be very appreciated!
Thanks.

Answer 1

You should handle the last char being whitespace or CR.
You also had a bug where you needed length – 1 in the for loop.

Here’s some working code:

    NSString *_text = [NSString stringWithString:@"line number 1\nline number 2\nlinenumber 3\n  "];

    // make sure you handle ending whitespace and ending carriage return
    _text = [_text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];

    NSUInteger i;
    unichar cr = '\n';
    for (i = [_text length] - 1; i>0; i--) 
    {
        if ([_text characterAtIndex:i] == cr) 
        {
            break;
        }
    }

    if (index > 0)
    {
        _text = [_text substringToIndex:i];
    }

    NSLog(@"%@", _text);

This outputs:
2011-09-22 08:00:10.473 Craplet[667:707] line number 1
line number 2