在TextFormField中插入Dash

本文介绍了在TextFormField中插入Dash的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 我有一个TextFormField，用户应在其中输入以下格式的字符串：I have a TextFormField where the user should enter a string in the following format: XX-XX-XX 无论如何，用户输入时是否会自动添加-？Is there anyway to automatically add the "-" as the user is typing?谢谢推荐答案这应该对您有用。class _MyHomePageState extends State<MyHomePage> { TextEditingController _controller = new TextEditingController(); @override void initState() { // TODO: implement initState super.initState(); // you can have different listner functions if you wish _controller.addListener(onChange); } @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text(widget.title), ), body: Container( child: Center( child: TextFormField( controller: _controller, ), ), ), ); } String newText = ''; void onChange(){ String text = _controller.text; if(text.length < newText.length) { // handling backspace in keyboard newText = text; }else if (text.isNotEmpty && text != newText) { // handling typing new characters. String tempText = text.replaceAll("-", ""); if(tempText.length % 2 == 0){ //do your text transforming newText = '$text-'; _controller.text = newText; _controller.selection = new TextSelection( baseOffset: newText.length, extentOffset: newText.length ); } } }} 这篇关于在TextFormField中插入Dash的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！