DART

Send HTTP POST request in Flutter or Dart

import 'dart:convert';
import 'package:http/http.dart' as http;

void main() async {
    http.Response response = await createUser("Bob", "engineer");
    
    print(response.body);
}

Future<http.Response> createUser(String name, String job) {
    return http.post(
        Uri.parse('https://reqres.in/api/users'),
        headers: <String, String>{
            'Content-Type': 'application/json; charset=UTF-8',
        },
        body: jsonEncode(<String, String>{
            'name': name,
            'job': job
        }),
    );
}

Send HTTP Get request in Flutter or Dart

import 'dart:convert';
import 'package:http/http.dart' as http;

void main {
    final response = await http.get(Uri.parse("https://domain.com/endpoint?data=hello"));

    String responseData = utf8.decode(response.bodyBytes);

    print(json.decode(responseData));
}

http post in flutter

dependencies:
  http: <latest_version>

How to send post request using http in flutter

import 'dart:async';
import 'dart:convert';
import 'dart:io';
import 'package:http/http.dart' as http;

Future<http.Response> postRequest () async {
  var url ='https://pae.ipportalegre.pt/testes2/wsjson/api/app/ws-authenticate';

  Map data = {
    'apikey': '12345678901234567890'
  }
  //encode Map to JSON
  var body = json.encode(data);

  var response = await http.post(url,
      headers: {"Content-Type": "application/json"},
      body: body
  );
  print("${response.statusCode}");
  print("${response.body}");
  return response;
}