SWIFT：Nstextfield仅允许指定的字符

Question

我需要有人向我展示如何在swift中允许nstexfield中的特定字符。例如，当用户尝试输入不在列表中的字符时，nstexfield将不会在字段中显示该字符。非常简单。有许多IOS示例，但找不到OSX示例。

Answer 1

首先将NSTextFieldDelegate添加到您的类......然后

添加：

 override func controlTextDidChange(obj: NSNotification) {
    let characterSet: NSCharacterSet = NSCharacterSet(charactersInString: " abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLKMNOPQRSTUVWXYZ0123456789-_").invertedSet
    self.textField.stringValue = (self.textField.stringValue.componentsSeparatedByCharactersInSet(characterSet) as NSArray).componentsJoinedByString("")
}

您必须将self.textfield替换为您想要控制的文本字段。

SWIFT 4编辑

 override func controlTextDidChange(_ obj: Notification) {
    let characterSet: NSCharacterSet = NSCharacterSet(charactersIn: " abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLKMNOPQRSTUVWXYZ0123456789-_").inverted as NSCharacterSet
    self.textField.stringValue =  (self.textField.stringValue.components(separatedBy: characterSet as CharacterSet) as NSArray).componentsJoined(by: "")
}

Answer 2

对于Swift 3：

override func controlTextDidChange(_ notification: Notification) {
    if textField == notification.object as? NSTextField {
        let characterSet: CharacterSet = (CharacterSet(charactersIn: "0123456789").inverted as NSCharacterSet) as CharacterSet
        textField.stringValue = (textField.stringValue.components(separatedBy: characterSet) as NSArray).componentsJoined(by: "")
    }
}