如何在Xcode中存储(在变量中)从数据库读取的Firestore文档数据

import Firebase

// ...

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    FirebaseApp.configure()
    return true
}

import FirebaseFirestore

// ...

let db = Firestore.firestore()
let docRef = db.collection("your_collection").document("your_document")

docRef.getDocument { (document, error) in
    if let document = document, document.exists {
        let data = document.data()
        // 在这里处理从文档中读取的数据
    } else {
        print("文档不存在")
    }
}

if let data = document.data() {
    let name = data["name"] as? String
    let age = data["age"] as? Int
    let hobbies = data["hobbies"] as? [String]
    
    // 在这里可以使用存储的数据
}