已经解决了，加上编码就行了

new Uri.dataFromString(snapshot.data, mimeType: 'text/html', encoding: Encoding.getByName('utf-8')).toString(),

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想请教一下，webview里加载本地html文件报错是什么情况呢？

加载webview的dart文件

import 'dart:io';

import 'package:flutter/widgets.dart';

import 'package:flutter/material.dart';

import 'package:flutter/services.dart' show rootBundle;

import 'package:flutter_webview_plugin/flutter_webview_plugin.dart';

class WebView extends StatefulWidget {

WebView({Key key}) : super(key: key);

@override

_WebViewState createState() => _WebViewState();

}

class _WebViewState extends State {

Future _getFile() async {

return await rootBundle.loadString('assets/index.html');

}

@override

Widget build(BuildContext context) {

return FutureBuilder(

future: _getFile(),

builder: (context, snapshot) {

if (snapshot.hasData) {

return WebviewScaffold(

appBar: AppBar(title: Text("Load HTM file in WebView")),

withJavascript: true,

appCacheEnabled: true,

withLocalUrl: true,

hidden: true,

allowFileURLs: true,

url: new Uri.dataFromString(snapshot.data, mimeType: 'text/html').toString(),

);

} else if (snapshot.hasError) {

return Scaffold(

body: Center(

child: Text("${snapshot.error}"),

),

);

}

return Scaffold(

body: Center(child: CircularProgressIndicator()),

);

},

);

}

}

pubspec.yaml

flutter:

uses-material-design: true

assets:

- assets/index.html

详细代码参考：