2022-04-26(显示服务端返回的emoji表情)

override func viewDidLoad() {
    super.viewDidLoad()
    
    let label = UILabel.init(frame: .init(x: 20, y: 200, width: 300, height: 60))
    label.backgroundColor = .init(red: 0.8, green: 0.4, blue: 0.2, alpha: 0.4)
    label.font = UIFont.systemFont(ofSize: 48)
    self.view.addSubview(label)
    
    let label2 = UILabel.init(frame: .init(x: 20, y: 280, width: 300, height: 60))
    label2.backgroundColor = .init(red: 0.6, green: 0.8, blue: 0.2, alpha: 0.4)
    label2.font = UIFont.systemFont(ofSize: 48)
    self.view.addSubview(label2)
    
// 情况一
    //  U+1F601
    //label.text = "\u{1F601}"
    //  U+1F1FA, U+1F1F8
    //label.text = "\u{1F1FA}\u{1F1F8}"
    // 
    label.text = "\u{1F601}\u{1F1FA}\u{1F1F8}"
    
// 情况二
    // 
    let emojiStr = "\\ud83c\\udde8\\ud83c\\uddf3"
    let str = "{\"emoji\":"+"\"\(emojiStr)\"}"
    let data = Data.init(bytes: str, count: str.count)
    let dic = try? JSONSerialization.jsonObject(with: data) as? [String : String]
    label2.text = dic?["emoji"]
}