【Swift 4.1】 UITextView 禁止输入Emoji表情，并且控制字数

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extension String{
/// 判断是不是Emoji
    ///
    /// - Returns: true false
    func containsEmoji()->Bool{
        for scalar in unicodeScalars {
            switch scalar.value {
            case 0x1F600...0x1F64F,
                 0x1F300...0x1F5FF,
                 0x1F680...0x1F6FF,
                 0x2600...0x26FF,
                 0x2700...0x27BF,
                 0xFE00...0xFE0F:
                return true
            default:
                continue
            }
        }

        return false
    }

/// 判断是不是Emoji
    ///
    /// - Returns: true false
    func hasEmoji()->Bool {

        let pattern = "[^\\u0020-\\u007E\\u00A0-\\u00BE\\u2E80-\\uA4CF\\uF900-\\uFAFF\\uFE30-\\uFE4F\\uFF00-\\uFFEF\\u0080-\\u009F\\u2000-\\u201f\r\n]"
        let pred = NSPredicate(format: "SELF MATCHES %@",pattern)
        return pred.evaluate(with: self)
    }

/// 判断是不是九宫格
    ///
    /// - Returns: true false
    func isNineKeyBoard()->Bool{
        let other : NSString = "➋➌➍➎➏➐➑➒"
        let len = self.length
        for i in 0 ..< len {
            if !(other.range(of: self).location != NSNotFound) {
                return false
            }
        }

        return true
    }


    /// 然后是去除字符串中的表情
    ///
    /// - Parameter text: text
    func disable_emoji(text : NSString)->String{
        do {
            let regex = try NSRegularExpression(pattern: "[^\\u0020-\\u007E\\u00A0-\\u00BE\\u2E80-\\uA4CF\\uF900-\\uFAFF\\uFE30-\\uFE4F\\uFF00-\\uFFEF\\u0080-\\u009F\\u2000-\\u201f\r\n]", options: NSRegularExpression.Options.caseInsensitive)

            let modifiedString = regex.stringByReplacingMatches(in: text as String, options: NSRegularExpression.MatchingOptions(rawValue: 0), range: NSMakeRange(0, text.length), withTemplate: "")

            return modifiedString
        } catch {
            print(error)
        }
        return ""
    }
}

UITextViewDelegate中
let limitMaxWord = 10

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {

        if text.isNineKeyBoard() {
            return true
        }else{
            if text.hasEmoji() || text.containsEmoji() {
                return false
            }
        }

        if textView.textInputMode?.primaryLanguage == "emoji" || !((textView.textInputMode?.primaryLanguage) != nil){
            return false
        }

        if text.length > 0 {
            quesDetualTextView.viewWithTag(8732)?.alpha = 0;
        }

        /// 选择区域
        if let selectedRange = textView.markedTextRange {
            if let pos = textView.position(from: selectedRange.start, offset: 0) {
                /// 获取高亮部分内容
                //        let selectedText = textView.text(in: selectedRange)
                let startOffset = textView.offset(from: textView.beginningOfDocument, to: selectedRange.start)
                let endOffset   = textView.offset(from: textView.beginningOfDocument, to: selectedRange.end)
                let offsetRange = NSMakeRange(startOffset, endOffset - startOffset)
                if offsetRange.location < limitMaxWord{
                    return true
                }else{
                    return false
                }
            }
        }

        let str = textView.text + text
        if str.length > limitMaxWord {
            let rangeIndex = (str as NSString).rangeOfComposedCharacterSequence(at: limitMaxWord)
            if rangeIndex.length == 1{
                textView.text = str.substringToIndex(limitMaxWord)
                textNumberLabel.text = "\(textView.text.length)/\(limitMaxWord)字"
            }else{
                let renageRange = (str as NSString).rangeOfComposedCharacterSequences(for: NSMakeRange(0, limitMaxWord))
                textView.text = str.substringWithRange(renageRange)

            }
            return false
        }
        return true
    }

func textViewDidChange(_ textView: UITextView) {

        /// 选择区域
        if let selectedRange = textView.markedTextRange {

            //获取高亮部分
            if let pos = textView.position(from: selectedRange.start, offset: 0) {
                //如果在变化中是高亮部分在变，就不要计算字符了
                return
            }
        }

        if textView.text.length > limitMaxWord {
            textView.text = textView.text.substringToIndex(limitMaxWord)
        }
        textNumberLabel.text = "\(textView.text.length)/\(limitMaxWord)字"
    }