Problem using NSRange: Index out of bounds

Question

I am trying to detect website URL's in my string and then doing some attribution string stuff like bolding it etc.

My regex is defined as:

static NSRegularExpression *websiteRegularExpression;
static inline NSRegularExpression * WebsiteRegularExpression() {
    if (!websiteRegularExpression) {
        websiteRegularExpression = [[NSRegularExpression alloc] initWithPattern:@"\b(https?|ftp|file)://[-A-Z0-9+&@#/%?=~_|!:,.;]*[A-Z0-9+&@#/%=~_|]" 
                                                                        options:NSRegularExpressionCaseInsensitive 
                                                                          error:nil];
    }

    return websiteRegularExpression;
}

Here is where I enumerate:

 -(void)setBodyText
    {
        __block NSRegularExpression *regexp = nil;    
        bodyLabel.delegate = self;
        [self.bodyLabel setText:@"http://www.google.com" afterInheritingLabelAttributesAndConfiguringWithBlock:^NSAttributedString *(NSMutableAttributedString *mutableAttributedString) {

            NSRange stringRange = NSMakeRange(0, [mutableAttributedString length]);

            regexp = WebsiteRegularExpression ();
            NSRange nameRange = [regexp rangeOfFirstMatchInString:[mutableAttributedString string] options:0 range:stringRange];
            UIFont *boldSystemFont = [UIFont boldSystemFontOfSize:18.0]; 
            CTFontRef boldFont = CTFontCreateWithName((CFStringRef)boldSystemFont.fontName, boldSystemFont.pointSize, NULL);
            if (boldFont) {
                [mutableAttributedString addAttribute:(NSString *)kCTFontAttributeName value:(id)boldFont range:nameRange];
                CFRelease(boldFont);
            }

            [mutableAttributedString replaceCharactersInRange:nameRange withString:[[[mutableAttributedString string] substringWithRange:nameRange] uppercaseString]];
            return mutableAttributedString;
        }];

        regexp = WebsiteRegularExpression();
        NSRange linkRange = [regexp rangeOfFirstMatchInString:self.bodyLabel.text options:0 range:NSMakeRange(0, [bodyLabel.text length])];
        [self.bodyLabel addLinkToURL:nil withRange:linkRange];
    }

I get the error:

*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[NSCFString substringWithRange:]: Range or index out of bounds'

How can I resolve?

can you post the regular expressions you are using? specifically what is mutableAttributedString. my guess is something is wrong in this line. [mutableAttributedString replaceCharactersInRange:nameRange withString:[[[mutableAttributedString string] substringWithRange:nameRange] uppercaseString]]; you might want to debug it by making sure each step is giving you want you expected. — madmik3, Jun 29 '11 at 03:08
I believe you are correct. I've updated my code with the regex. Still not sure how to resolve... — Sheehan Alam, Jun 29 '11 at 03:31

RedBlueThing · Accepted Answer · 2011-06-29T03:44:45.493

10

Check the contents of nameRange before you call substringWithRange. If your regular expression doesn't match then the return value for rangeOfFirstMatchInString will be

{NSNotFound, 0}

NSNotFound is defined as NSIntegerMax so you can imagine why this value might be out of range for your mutableAttributedString.

Update for comment

So to check the results of substringWithRange:

if (nameRange.location == NSNotFound)
    // didn't match the WebsiteRegularExpression() do something else

edited Jun 29 '11 at 03:44

answered Jun 29 '11 at 03:05

RedBlueThing

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how can I check the contents of nameRange? – Sheehan Alam Jun 29 '11 at 03:39
@sheehan-alam just check the location member on the range object (see update). – RedBlueThing Jun 29 '11 at 03:45

score 4 · Answer 2 · edited Jun 29 '11 at 03:10

4

Nowhere are you checking to see if any range you got back has the range.location = NSNotFound. One of your matches is coming up empty and then you are trying to use the range for other things.

edited Jun 29 '11 at 03:10

Lily Ballard

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answered Jun 29 '11 at 03:04

Kendall Helmstetter Gelner

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I am pretty new to NSRange, can you show me an example of how I could perform this check in my code? – Sheehan Alam Jun 29 '11 at 03:39
2

Since RedBlue beat me to the response, I just up voted his answer. – Kendall Helmstetter Gelner Jun 29 '11 at 03:46

Problem using NSRange: Index out of bounds

2 Answers2

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