flutter ---TextField 之 输入类型、长度限制

TextField想要实现输入类型、长度限制需要先引入import ‘package:flutter/services.dart’;
例如

import 'package:flutter/services.dart';

TextField(
       keyboardType: TextInputType.number,//键盘类型，数字键盘
       style: TextStyle(fontSize: ScreenUtil().setWidth(40), color: Colors.black),//输入文字样式
       controller: _cpyCode,//控制器
       decoration: InputDecoration(
       		hintText: '请输入6位公司编号',
       		hintStyle: TextStyle( fontWeight: FontWeight.w600, fontSize: ScreenUtil().setWidth(40), color: 			   Colors.grey[400]),
           border: InputBorder.none,
       ),
       inputFormatters: <TextInputFormatter>[
           WhitelistingTextInputFormatter.digitsOnly,//只输入数字
           LengthLimitingTextInputFormatter(6)//限制长度
       ],
       onChanged: _listenCpyCode,
)),