不搜索第一个字母

Question

我正在将我的 plist 加载到 TableView 中，一切正常，但是现在当我搜索某些内容时，它不会考虑第一个字母。下面你会看到 directory.plist 和我的 Main.storyboard

为了正确加载 plist，我将以下代码放在我的 didFinishLaunchingWithOptions 上：

class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        if let url = Bundle.main.url(forResource: "directory", withExtension: "plist"), let array = NSArray(contentsOf: url) as? [[String:Any]] {
            Shared.instance.employees = array.map{Employee(dictionary: $0)}
        }
        return true
}

我还有一个结构可以帮助我加载我所有的东西：

struct EmployeeDetails {
    let functionary: String
    let imageFace: String
    let phone: String

    init(dictionary: [String: Any]) {
        self.functionary = (dictionary["Functionary"] as? String) ?? ""
        self.imageFace = (dictionary["ImageFace"] as? String) ?? ""
        self.phone = (dictionary["Phone"] as? String) ?? ""
    }
}
struct Employee {
    let position: String
    let name: String
    let details: [EmployeeDetails] // [String:Any]

    init(dictionary: [String: Any]) {
        self.position = (dictionary["Position"] as? String) ?? ""
        self.name = (dictionary["Name"] as? String) ?? ""
    
        let t = (dictionary["Details"] as? [Any]) ?? []
        self.details = t.map({EmployeeDetails(dictionary: $0 as! [String : Any])})
    }
}

struct Shared {
    static var instance = Shared()
    var employees: [Employee] = []
}

到这里为止，一切都运行良好！现在我在尝试插入 SearchView 时遇到了麻烦，看看我到目前为止做了什么：

class Page1: UITableViewController, UISearchBarDelegate {
    
    @IBOutlet weak var searchBar: UISearchBar!
    
    var employeesSearching = [Employee]()
    var isSearching : Bool = false

    override func viewDidLoad() {
        super.viewDidLoad()
        
        self.searchBar.delegate = self
    }
    
    override func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }
    
    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        if self.isSearching == true {
            return self.employeesSearching.count
        } else {
            return Shared.instance.employees.count
        }
    }

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! TableViewCell1
        let employee = Shared.instance.employees[indexPath.row]
        
        if self.isSearching == true {
            cell.nameLabel.text = self.employeesSearching[indexPath.row].name
            cell.positionLabel.text = self.employeesSearching[indexPath.row].position
        } else {
            cell.nameLabel.text = employee.name
            cell.positionLabel.text = employee.position
        }
        return cell
    }
    
    func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
        if self.searchBar.text!.isEmpty {
            self.isSearching = false
            self.tableView.reloadData()
        } else {
            self.isSearching = true
            self.employeesSearching.removeAll(keepingCapacity: false)
            for i in 0..<Shared.instance.employees.count {
                let listItem : Employee = Shared.instance.employees[i]
                if listItem.name.range(of: self.searchBar.text!.lowercased()) != nil {
                    self.employeesSearching.append(listItem)
                }
            }
            self.tableView.reloadData()
        }
    }
    
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if let destination = segue.destination as? Page2,
            let indexPath = tableView.indexPathForSelectedRow {
            destination.newPage = Shared.instance.employees[indexPath.row]
        }
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }
}

我在搜索的第一个字母时遇到问题。看看：

Answer 1

问题出在这一行：

if listItem.name.range(of: self.searchBar.text!.lowercased()) != nil {

您正在员工姓名的常规文本中查找搜索文本的小写版本。

文本“John Smith”不包含搜索文本“j”。但它确实包含搜索文本“ohn”。

快速解决方法是将该行代码更改为：

if listItem.name.lowercased().range(of: self.searchBar.text!.lowercased()) != nil {

现在比较员工姓名和搜索文本的小写版本。所以现在它会匹配，因为“john smith”包含“j”。

顺便说一句 - 一遍又一遍地小写搜索文本效率低下。还有一种更好的方法来编写循环代码。我会将其更改为：

self.employeesSearching.removeAll(keepingCapacity: false)
let searchText = self.searchBar.text!.lowercased()
for employee in Shared.instance.employees {
    if employee.name.lowercased().range(of: searchText) != nil {
        self.employeesSearching.append(employee)
    }
}

更简单的方法是将代码替换为：

let searchText = self.searchBar.text!.lowercased()
self.employeesSearching = Shared.instance.employees.filter { $0.name.lowercased().range(of: searchText) != nil
}

要搜索名称或位置的文本，只需更新比较表达式：

if employee.name.lowercased().range(of: searchText) != nil || employee.position.lowercased().range(of: searchText) != nil {

如果您使用filter，请进行类似的更改。