Question

在我的应用中，我有2个文本字段。 taskTextField和DescTextField。我想将任务文本字段的字符限制为15，将描述文本字段限制为20.我已设法限制两者但我不知道如何单独执行它们。这是我的代码：

let limitLength = 20

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
    guard let text = textField.text else { return true }
    let newLength = text.characters.count + string.characters.count - range.length
    return newLength <= limitLength
}

任何有关如何为每个文本字段制定单独限制的帮助都将不胜感激。

Answer 1

为每个UITextField添加标记：

let taskTextFieldTag = 100
let DescTextFieldTag = 101

override func viewDidLoad() {

     // ..

     taskTextField.tag = taskTextFieldTag
     DescTextField.tag = DescTextFieldTag

     // ...
}

在UITextFieldDelegate：

中

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {

    guard let text = textField.text else {
        return false
    }

    let newLength = text.utf16.count + string.utf16.count - range.length

    var maxLength = 0

    switch textField.tag {
    case taskTextFieldTag:
         maxLength = 15
    case DescTextFieldTag:
         maxLength = 20
    default: break
    }

    return newLength <= maxLength
}

Answer 2

基于您的代码，假设您可以通过IBOutlets将文本字段连接到您的代码

    @IBOutlet weak var taskTextField: UITextField!
    @IBOutlet weak var descTextField: UITextField!

    let taskTextFieldlimitLength = 15
    let descTextFieldlimitLength = 20

    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        switch textField {
        case taskTextField:
            guard let text = textField.text else { return true }
            let newLength = text.characters.count + string.characters.count - range.length
            return newLength <= taskTextFieldlimitLength
        case descTextField:
            guard let text = textField.text else { return true }
            let newLength = text.characters.count + string.characters.count - range.length
            return newLength <= descTextFieldlimitLength
        default:
            return true
        }
    }

在2个单独的文本字段中限制字符Swift 3

2 个答案: