Question

I’m having a hard time with trimming some characters from a NSString. Given an existing text view with text in it, the requirements are:

1. Trim leading spaces and newlines (Basically ignore any leading whitespace and newlines)
2. Copy up to max of 48 chars into the new string OR until a newline is encountered.

I have found that I could do the first requirement from another SO question here with the code:

NSRange range = [textView.text rangeOfString:@"^\\s*" options:NSRegularExpressionSearch];
NSString *result = [textView.text stringByReplacingCharactersInRange:range withString:@""];

However, I’m having trouble with doing the 2nd requirement. Thank you!

Answer 1

This will do what your looking to do. Also it is an easier way to trim leading whitespace and newlines.

NSString *text = textView.text;

//remove any leading or trailing whitespace or line breaks
text = [text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];

//find the the range of the first occuring line break, if any.
NSRange range = [text rangeOfString:@"\n"];

//if there is a line break, get a substring up to that line break
if(range.location != NSNotFound)
    text = [text substringToIndex:range.location];
//else if the string is larger than 48 characters, trim it
else if(text.length > 48)
    text = [text substringToIndex:48];