Question

我想从用户阵列获取姓名和电子邮件，但我收到错误＆＃34;输入任何内容？没有下标成员＆＃34;

NewMessController.swift中的

class NewMessagesViewController: UITableViewController {
    let cellID = "cellId"
    var user = [Users]()

    override func viewDidLoad() {
        super.viewDidLoad()
        navigationItem.leftBarButtonItem = UIBarButtonItem.init(title: "Cancel", style: .plain, target: self, action: #selector(handleCancel))

        fetchUser()
    }

    func fetchUser(){
        let rootRef = FIRDatabase.database().reference()
        let query = rootRef.child("users").queryOrdered(byChild: "name")
        query.observe(.value) { (snapshot) in
            for child in snapshot.children.allObjects as! [FIRDataSnapshot] {
                if let value = child.value as? NSDictionary {
                    let user = Users()
                    let name = value["name"] as? String ?? "Name not found"
                    let email = value["email"] as? String ?? "Email not found"
                    user.name = name
                    user.email = email
                    self.user.append(user)
                    DispatchQueue.main.async { self.tableView.reloadData() }
                }
            }
        }
    }

    @objc func handleCancel(){
        dismiss(animated: true, completion: nil)
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return user.count
    }

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = UITableViewCell(style: .subtitle, reuseIdentifier: cellID)
        let user = Users[indexPath.row]
        cell.textLabel?.text = user.name //error here
        return cell
    }

}

并在Users.swift中导入UIKit

class Users: NSObject {
    var name:String?
    var email:String?
}

如何修复它并获取名称和电子邮件？非常感谢。

Answer 1

尝试回复userData.value(forKey: "name") as? String。

func fetchUser(){
        let rootRef = FIRDatabase.database().reference()
        let query = rootRef.child("users").queryOrdered(byChild: "name")
        query.observe(.value) { (snapshot) in

            DispatchQueue.main.async {

                for child in snapshot.children.allObjects as! [FIRDataSnapshot] {
                    if let userData = child.value as? NSDictionary {
                        let user = Users()
                        let name = userData.value(forKey: "name") as? String ?? "Name not found"
                        let email = userData.value(forKey: "email") as? String ?? "Email not found"
                        user.name = name
                        user.email = email
                        self.user.append(user)
                    }
                }
                self.tableView.reloadData()
            }
        }
    }

输入＆＃39; Users.Type＆＃39;没有下标成员

1 个答案: