How to trim(remove) white spaces from end of a NSAttributedString

Swift answer but it give you a start if you translate it to Obj-C (or make a swift file just with the extension for use in your Obj-C then)

extension NSMutableAttributedString {

    func trimmedAttributedString(set: CharacterSet) -> NSMutableAttributedString {

        let invertedSet = set.inverted

        var range = (string as NSString).rangeOfCharacter(from: invertedSet)
        let loc = range.length > 0 ? range.location : 0

        range = (string as NSString).rangeOfCharacter(
                            from: invertedSet, options: .backwards)
        let len = (range.length > 0 ? NSMaxRange(range) : string.characters.count) - loc

        let r = self.attributedSubstring(from: NSMakeRange(loc, len))
        return NSMutableAttributedString(attributedString: r)
    }
}

Usage :

let noSpaceAttributedString =
   attributedString.trimmedAttributedString(set: CharacterSet.whitespacesAndNewlines)

Swift 4 and above

we can create extension on NSMutableAttributedString which returns new NSAttributedString by removing .whitespacesAndNewlines

extension NSMutableAttributedString {

    func trimmedAttributedString() -> NSAttributedString {
        let invertedSet = CharacterSet.whitespacesAndNewlines.inverted
        let startRange = string.rangeOfCharacter(from: invertedSet)
        let endRange = string.rangeOfCharacter(from: invertedSet, options: .backwards)
        guard let startLocation = startRange?.upperBound, let endLocation = endRange?.lowerBound else {
            return NSAttributedString(string: string)
        }
        let location = string.distance(from: string.startIndex, to: startLocation) - 1
        let length = string.distance(from: startLocation, to: endLocation) + 2
        let range = NSRange(location: location, length: length)
        return attributedSubstring(from: range)
    }
}