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I am using aqueduct web api framework to support my flutter app. In my api backend I need to connect local network socket services. My problem is that I can't return the exact string (in tr). S o, How can I convert string to utf8 in Dart?

Example:

@httpGet
Future<Response> getLogin() async {
    Socket.connect('192.168.1.22', 1024).then((socket) async {
    socket.listen((data) {
        // Expected return is: 1:_:2:_:175997:_:NİYAZİ TOROS
        print(new String.fromCharCodes(data).trim());
        xResult = new String.fromCharCodes(data).trim();
        print("xResult: $xResult");
    }, onDone: () {
        print("Done");
        socket.destroy();
    socket.write('Q101:_:49785:_:x\r\n');
    return new Response.ok(xResult);
The return is not in TR-tr language format.
Return text looks like:
**1:_:2:_:175997:_:NÝYAZÝ TOROS**
Correct must be:
**1:_:2:_:175997:_:NİYAZİ TOROS**
UPDATE:
xResult = new String.fromCharCodes(data).trim();
print(xResult);
responseBody = xResult.transform(utf8.decoder);
print(responseBody);
I can print the xResult but cannot print the responseBody after trying convert to UTF8
                in the 4. step is not printing. means responseBody is null, meaning utf8.decoder didn't do anything
– user9239214
                Jun 29, 2018 at 12:56
                Ok. I cenge it to responseBody = utf8.decode(xResult); and still can't print responseBody
– user9239214
                Jun 29, 2018 at 13:19
import 'dart:convert' show utf8;
var encoded = utf8.encode('Lorem ipsum dolor sit amet, consetetur...');
var decoded = utf8.decode(encoded);
See also https://api.dartlang.org/stable/1.24.3/dart-convert/UTF8-constant.html
There are also encoder and decoder to be used with streams
File.openRead().transform(utf8.decoder).
See also https://www.dartlang.org/articles/libraries/converters-and-codecs#converter
                List<int> fileBytes = await file.readAsBytes(); Then used the utf8.decode(fileBytes). works as per the requirement. :)
– Rakesh Verma
                Dec 22, 2022 at 13:33
 void handleConnection(Socket client) {
print('Connection from'
    ' ${client.remoteAddress.address}:${client.remotePort}');
// listen for events from the client
client.listen(
  // handle data from the client
  (Uint8List data) async {
    await Future.delayed(Duration(seconds: 1));
    final message =  utf8.decode(data);
    // final message = String.fromCharCodes(data);
    int length = messageWidgets.length;
    Widget padding2 = Padding(
      padding: const EdgeInsets.all(8.0),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.start,
        children: [
          Expanded(
            flex: 1,
            child: GestureDetector(
                onLongPress: () {
                  _copy(message);
                onDoubleTap: () {
                  setState(() {
                    messageWidgets.removeAt(length);
                child: Container(
                  padding: EdgeInsets.all(8.0),
                  decoration: BoxDecoration(
                    borderRadius: BorderRadius.circular(10),
                    color: Color(0xDD44871F),
                  child: Stack(
                    children: <Widget>[
                      Column(
                        // direction: Axis.vertical,
                        children: [
                          Text("${client.remoteAddress.host}::-",
                              style: TextStyle(color: Colors.black87)),
                          Text("${message}",
                              style: TextStyle(color: Colors.black87)),
          Expanded(
            flex: 1,
            child: Container(),
    setState(() {
      messageWidgets.add(padding2);
  // handle errors
  onError: (error) {
    print(error);
    setMwidget(error);
    client.close();
  // handle the client closing the connection
  onDone: () {
    print('Client left');
    client.close();
This is not the solution for your specific case but relative to the title.
If your string is a Uri, use:
final decodedUri = Uri.decodeFull('your-string-uri')
Android string Uri is an example use case, here is a demo before and after using Uri.decodeFull():
To/from Uint8List
//Uint8List to String
Uint8List bytes = utf8.encode(String s) as Uint8List;
//String to Uint8List
String s = utf8.decode(bytes.toList());
Uint8List myUint8List = utf8.encode('yourTextHere') as Uint8List;
// List<int> to Uint8List:
Uint8List myUint8List = Uint8List.fromList(byteIntList);
        
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