How to limit special characters in textinput in Flutter?

Question

I want to use only Alphabat, space and "-" for name input using "Textinput".

Usage:- For user name input we don't want to allow user to enter "(,),$,%,&,*" characters.

Answer 1

Update WhitelistingTextInputFormatter is depreacted now please use FilteringTextInputFormatter

Example

    inputFormatters: [FilteringTextInputFormatter.allow(RegExp(r'^ ?\d*')),]
    inputFormatters: [FilteringTextInputFormatter.deny(' ')]
    inputFormatters: [FilteringTextInputFormatter.digitsOnly]

You can use WhitelistingTextInputFormatter for input text as you expect with RegExp.

                    TextFormField(
                        controller: _titleTextController,
                        validator: _titleValidator,
                        decoration: InputDecoration(
                            labelText: "Title",
                            suffixIcon: GestureDetector(
                              onTap: () {
                                setState(() {
                                  _titleTextController.text ="";
                                });
                              },
                              child: Icon(Icons.clear),
                            )
                        ),
                        inputFormatters: [
                        // @depreacted WhitelistingTextInputFormatter(RegExp("[a-zA-Z -]"))
                         inputFormatters: [FilteringTextInputFormatter.allow(RegExp("[a-zA-Z -]"))]
                        ],
                      )

For more you can refer this : https://api.flutter.dev/flutter/services/TextInputFormatter-class.html