TextViewの選択中の文字列を取得する方法

func textViewDidChangeSelection(_ textView: UITextView) {

        let location = textView.selectedRange.location
        let length = textView.selectedRange.length
        let text = (textView.text as NSString).substring(with: NSRange(location:location,length: length))
        print(location)
        print(length)
        print(text)

    }

参照

【swift】uitextviewの選択範囲の文字列を取得する方法
How to restrict cursor position in swift?