在两个单独的文本域中限制字符Swift 3

Question

在我的应用程序中，我有两个文本字段。 taskTextField和DescTextField。我想将任务文本字段的字符限制为15，并将描述文本字段限制为20.我设法限制了这两个字段，但我不知道如何单独执行它们。这里是我的两个代码：

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 
} 

如何为每个文本字段单独限制任何帮助，将不胜感激。

Answer 1

1. 添加标签为每个UITextField：

   let taskTextFieldTag = 100 
   let DescTextFieldTag = 101 
   
   override func viewDidLoad() { 
   
       // .. 
   
       taskTextField.tag = taskTextFieldTag 
       DescTextField.tag = DescTextFieldTag 
   
       // ... 
   } 
   

2. 在UITextFieldDelegate：基于您的代码

   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

假设您可以将文本字段连接到您的代码通过IBOutlets

@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 
     } 
    }