在dart:io中使用json content-type的Http POST请求

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在dart:io中使用json content-type的Http POST请求

mobiledu2502895137 发布于 2022-12-04 13:44

如何使用控制台dart应用程序执行HTTP POST(使用dart:io或可能是package:http库.我这样做:

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

  http.post(
    url,
    headers: {HttpHeaders.CONTENT_TYPE: "application/json"},
    body: {"foo": "bar"})
      .then((response) {
        print("Response status: ${response.statusCode}");
        print("Response body: ${response.body}");
      }).catchError((err) {
        print(err);
      });



但是得到以下错误:

Bad state: Cannot set the body fields of a Request with content-type "application/json".

    
  




  
  
  

    

      

        小智..
         29
      
      
这是一个完整的例子.您必须使用json.encode(...)将请求的主体转换为JSON.

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


var url = "https://someurl/here";
var body = json.encode({"foo": "bar"});

Map headers = {
  'Content-type' : 'application/json', 
  'Accept': 'application/json',
};

final response =
    http.post(url, body: body, headers: headers);
final responseJson = json.decode(response.body);
print(responseJson);


通常建议您使用a Future来满足您的要求,这样您就可以尝试类似的东西

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

Future requestMethod() async {
    var url = "https://someurl/here";
    var body = json.encode({"foo": "bar"});

    Map headers = {
      'Content-type' : 'application/json', 
      'Accept': 'application/json',
    };

    final response =
        await http.post(url, body: body, headers: headers);
    final responseJson = json.decode(response.body);
    print(responseJson);
    return response;
}


语法的唯一区别是async和await关键字.



        
        2 个回答
        
                        
                来自http.dart:


///[body]setsthebodyoftherequest.Itcanbea[String],a[List<int>]or
///a[Map<String,String>].IfitsaString,itsencodedusing[encoding]and
///usedasthebodyoftherequest.Thecontent-typeoftherequestwill
///defaulttotext/plain.



所以自己生成JSON主体(使用JSON.encodefromdart:convert).

                
                    2022-12-11 01:55  回答
                       品位人生2602905223
                
            
                        
                这是一个完整的例子.您必须使用json.encode(...)将请求的主体转换为JSON.

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


var url = "https://someurl/here";
var body = json.encode({"foo": "bar"});

Map headers = {
  'Content-type' : 'application/json', 
  'Accept': 'application/json',
};

final response =
    http.post(url, body: body, headers: headers);
final responseJson = json.decode(response.body);
print(responseJson);


通常建议您使用a Future来满足您的要求,这样您就可以尝试类似的东西

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

Future<http.Response> requestMethod() async {
    var url = "https://someurl/here";
    var body = json.encode({"foo": "bar"});

    Map<String,String> headers = {
      'Content-type' : 'application/json', 
      'Accept': 'application/json',
    };

    final response =
        await http.post(url, body: body, headers: headers);
    final responseJson = json.decode(response.body);
    print(responseJson);
    return response;
}


语法的唯一区别是async和await关键字.

        
                
                    2022-12-11 02:57  回答
                       是你让我变得冷漠涡
                
            
                    
    
    
    
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