Flutter 請求網(wǎng)絡(luò)的三種方式
flutter 請求網(wǎng)絡(luò)的方式有三種,分別是 Dart 原生的網(wǎng)絡(luò)請求 HttpClient、第三方網(wǎng)絡(luò)請求 http以及 Flutter 中的 Dio。我們可以比較一下這三種網(wǎng)絡(luò)請求方式,然后封裝為我們方便請求網(wǎng)絡(luò)的工具類。
Dart 原生的網(wǎng)絡(luò)請求 HttpClient
實(shí)現(xiàn) Dart 獲取網(wǎng)絡(luò)數(shù)據(jù)的請求,一般我們需要以下幾個步驟:
- step 1: 原生的網(wǎng)絡(luò)請求時不需要修改 pubspec.yaml 文件的,我們只需要在使用的地方引入所需包就可以了
import 'dart:convert';
import 'dart:io';
- step 2:創(chuàng)建一個HttpClient
HttpClient httpClient = new HttpClient();
- step 3: 打開Http連接,設(shè)置請求頭
HttpClientRequest request = await httpClient.getUrl(uri);
在這一步中,我們可以設(shè)置人意的的請求方法,比如 Get 請求、Post 請求、Delete 請求。
例如:攜帶參數(shù)的請求
Uri uri=Uri(scheme: "https", host: "flutterchina.club", queryParameters: {
"userName":"chen",
"password":"123456"
});
例如:設(shè)置請求的 header
request.headers.add("user-agent", "test");
request.headers.add("Authorization", "LKSJDLFJSDLKJSLKklsdj");
- step 4: 等待連接服務(wù)器
HttpClientResponse response = await request.close();
- step 5: 讀取響應(yīng)內(nèi)容
if (response.statusCode == HttpStatus.ok) {
_content = await response.transform(Utf8Decoder()).join();
}
- step 6: 斷開連接
httpClient.close();
以上的步驟是 dart 簡單獲取網(wǎng)絡(luò)的方式,我們從上面可以看到,通過 HttpClient 發(fā)起網(wǎng)絡(luò)請求時比較麻煩的,很多都要我們親手處理,還有 Cookie 的管理也是比較麻煩的。
庫 http
-
step 1:pubspec.yaml 添加依賴
http: '>=0.11.3+12'
-
step 2: 在使用的地方導(dǎo)包
import 'package:http/http.dart' as http;
step 3: 發(fā)起請求
Get 請求
void getRequest() async {
var client = http.Client();
http.Response response = await client.get(url_2);
_content = response.body;
}
Post 請求
void postRequest() async {
var params = Map<String, String>();
params["username"] = "hellonews";
params["password"] = "123456";
var client = http.Client();
var response = await client.post(url_post, body: params);
_content = response.body;
}
相對比 Dart 原生的網(wǎng)絡(luò)請求,第三方庫 http 的網(wǎng)絡(luò)請求方式是要方便好多,寫起來也是挺爽的。
Flutter 發(fā)布的 dio
Dio 一個強(qiáng)大的 Dart Http 請求庫,支持 Restful API、FormData、攔截器、請求取消、Cookie管理、文件上傳/下載、超時等...
- 1:pubspec.yaml 添加依賴
dependencies:
dio: ^1.0.9
- step 2:導(dǎo)入引用包
import 'package:dio/dio.dart';
- step 3:發(fā)起網(wǎng)絡(luò)請求
Get 請求
void getRequest() async {
Dio dio = new Dio();
var response = await dio.get("/test?id=12&name=chen");
_content = response.data.toString();
}
對于 query 參數(shù),我們可以通過對象來進(jìn)行傳遞,上面的代碼等同于:
void getRequest() async {
Dio dio = new Dio();
var response = await dio.get("/test",data:{"id":12,"name":"chen"});
_content = response.data.toString();
}
Post 請求
void postRequest() async {
var dio = new Dio();
var response = await dio.post(url_post, data:{"id":12,"name":"wendu"});
_content = response.data.toString();
}
Dio 網(wǎng)絡(luò)請求框架封裝
日志信息攔截
Dio 和 okhttp 一樣,都會有一個請求攔截器和響應(yīng)攔截器,通過攔截器,我們可以在請求之前或響應(yīng)之后做一些同意的預(yù)處理。例如我們發(fā)起請求前查看我們請求的參數(shù)和頭部,響應(yīng)的時候,我們可以查看返回來的數(shù)據(jù)。
Dio dio = new Dio();
// 添加攔截器
if (Config.DEBUG) {
dio.interceptors.add(InterceptorsWrapper(
onRequest: (RequestOptions options){
print("\n================== 請求數(shù)據(jù) ==========================");
print("url = ${options.uri.toString()}");
print("headers = ${options.headers}");
print("params = ${options.data}");
},
onResponse: (Response response){
print("\n================== 響應(yīng)數(shù)據(jù) ==========================");
print("code = ${response.statusCode}");
print("data = ${response.data}");
print("\n");
},
onError: (DioError e){
print("\n================== 錯誤響應(yīng)數(shù)據(jù) ======================");
print("type = ${e.type}");
print("message = ${e.message}");
print("stackTrace = ${e.stackTrace}");
print("\n");
}
));
}
如果我們想要移除攔截器,那么我們可以將其設(shè)置為 null
dio.interceptor.request.onSend=null;
dio.interceptor.response.onSuccess=null;
dio.interceptor.response.onError=null;
token 添加
// 頭部添加 token 驗(yàn)證
headers["Authorization"] = "token lskjdlklsjkdklsjd333";
option.headers = headers;
///超時
option.connectTimeout = 15000;
try {
Response response = await dio.request(url, data: params, options: option);
} on DioError catch (e) {
// 請求錯誤處理
}
自動生成 dart 的 json 實(shí)體類插件 FlutterJsonBeanFactory
在 Android 開發(fā)中,有 GsonFormat 這個插件來講 json 數(shù)據(jù)自動轉(zhuǎn)化成 Bean;那么在 Flutter 中也有類似的插件可以生產(chǎn)序列化的實(shí)體類的插件:FlutterJsonBeanFactory
- step 1:下載插件 FlutterJsonBeanFactory,安裝完成后重啟
Setting -> Plugins -> Browse Respositories 中搜索 FlutterJsonBeanFactory
- step 2:創(chuàng)建實(shí)體類,在指定目錄下:
New -> dart bean class File from JSON
-
step 3:輸入實(shí)體類名及 json 格式的數(shù)據(jù)
image.png step 4:最后生成的實(shí)體類:LoginEntity
class LoginEntity {
String easemobpassword;
String username;
LoginEntity({this.easemobpassword, this.username});
LoginEntity.fromJson(Map<String, dynamic> json) {
easemobpassword = json['easemobPassword'];
username = json['username'];
}
Map<String, dynamic> toJson() {
final Map<String, dynamic> data = new Map<String, dynamic>();
data['easemobPassword'] = this.easemobpassword;
data['username'] = this.username;
return data;
}
}
請求錯誤處理
Response response;
try {
response = await dio.request(url, data: params, options: option);
} on DioError catch (e) {
// 請求錯誤處理
Response errorResponse;
if (e.response != null) {
errorResponse = e.response;
} else {
errorResponse = new Response(statusCode: 666);
}
if (e.type == DioErrorType.CONNECT_TIMEOUT) {
errorResponse.statusCode = Code.NETWORK_TIMEOUT;
}
if (Config.DEBUG) {
print('請求異常: ' + e.toString());
print('請求異常 url: ' + url);
}
return new ResultData(Code.errorHandleFunction(errorResponse.statusCode, e.message, noTip), false, errorResponse.statusCode);
}
其中 ResultData 是網(wǎng)絡(luò)結(jié)果處理的實(shí)體類
/**
* 網(wǎng)絡(luò)結(jié)果數(shù)據(jù)
* Created by chenjianrun
* Date: 2018-07-16
*/
class ResultData {
var data;
bool result;
int code;
var headers;
ResultData(this.data, this.result, this.code, {this.headers});
}
Code 是處理網(wǎng)絡(luò)錯誤的編碼,并將錯誤結(jié)果通過 eventbus 發(fā)送出去,一般我們可以在 main_pager 中注冊監(jiān)聽這個事件。
///網(wǎng)絡(luò)請求錯誤編碼
class Code {
///網(wǎng)絡(luò)錯誤
static const NETWORK_ERROR = -1;
///網(wǎng)絡(luò)超時
static const NETWORK_TIMEOUT = -2;
///網(wǎng)絡(luò)返回?cái)?shù)據(jù)格式化一次
static const NETWORK_JSON_EXCEPTION = -3;
static const SUCCESS = 200;
static final EventBus eventBus = new EventBus();
static errorHandleFunction(code, message, noTip) {
if(noTip) {
return message;
}
eventBus.fire(new HttpErrorEvent(code, message));
return message;
}
}
完成的網(wǎng)絡(luò)請求類:HttpRequest
import 'dart:io';
import 'package:dio/dio.dart';
import 'package:private_tutor/common/SpUtils.dart';
import 'package:connectivity/connectivity.dart';
import 'dart:collection';
import 'package:private_tutor/common/config/Config.dart';
import 'package:private_tutor/net/ResultCode.dart';
import 'package:private_tutor/net/ResultData.dart';
///http請求管理類,可單獨(dú)抽取出來
class HttpRequest {
static String _baseUrl;
static const CONTENT_TYPE_JSON = "application/json";
static const CONTENT_TYPE_FORM = "application/x-www-form-urlencoded";
static Map optionParams = {
"timeoutMs": 15000,
"token": null,
"authorizationCode": null,
};
static setBaseUrl(String baseUrl){
_baseUrl = baseUrl;
}
static get(url,param) async{
return await request(_baseUrl+url, param, null, new Options(method:"GET"));
}
static post(url,param) async{
return await request(_baseUrl+url, param, {"Accept": 'application/vnd.github.VERSION.full+json'}, new Options(method: 'POST'));
}
static delete(url,param) async{
return await request(_baseUrl+url, param, null, new Options(method: 'DELETE'));
}
static put(url,param) async{
return await request(_baseUrl+url, param, null, new Options(method: "PUT", contentType: ContentType.text));
}
///發(fā)起網(wǎng)絡(luò)請求
///[ url] 請求url
///[ params] 請求參數(shù)
///[ header] 外加頭
///[ option] 配置
static request(url, params, Map<String, String> header, Options option, {noTip = false}) async {
//沒有網(wǎng)絡(luò)
var connectivityResult = await (new Connectivity().checkConnectivity());
if (connectivityResult == ConnectivityResult.none) {
return new ResultData(Code.errorHandleFunction(Code.NETWORK_ERROR, "", noTip), false, Code.NETWORK_ERROR);
}
Map<String, String> headers = new HashMap();
if (header != null) {
headers.addAll(header);
}
//授權(quán)碼
if (optionParams["authorizationCode"] == null) {
var authorizationCode = await getAuthorization();
if (authorizationCode != null) {
optionParams["authorizationCode"] = authorizationCode;
}
}
headers["Authorization"] = optionParams["authorizationCode"];
// 設(shè)置 baseUrl
if (option != null) {
option.headers = headers;
} else{
option = new Options(method: "get");
option.headers = headers;
}
///超時
option.connectTimeout = 15000;
Dio dio = new Dio();
// 添加攔截器
if (Config.DEBUG) {
dio.interceptors.add(InterceptorsWrapper(
onRequest: (RequestOptions options){
print("\n================== 請求數(shù)據(jù) ==========================");
print("url = ${options.uri.toString()}");
print("headers = ${options.headers}");
print("params = ${options.data}");
},
onResponse: (Response response){
print("\n================== 響應(yīng)數(shù)據(jù) ==========================");
print("code = ${response.statusCode}");
print("data = ${response.data}");
print("\n");
},
onError: (DioError e){
print("\n================== 錯誤響應(yīng)數(shù)據(jù) ======================");
print("type = ${e.type}");
print("message = ${e.message}");
print("stackTrace = ${e.stackTrace}");
print("\n");
}
));
}
Response response;
try {
response = await dio.request(url, data: params, options: option);
} on DioError catch (e) {
// 請求錯誤處理
Response errorResponse;
if (e.response != null) {
errorResponse = e.response;
} else {
errorResponse = new Response(statusCode: 666);
}
if (e.type == DioErrorType.CONNECT_TIMEOUT) {
errorResponse.statusCode = Code.NETWORK_TIMEOUT;
}
if (Config.DEBUG) {
print('請求異常: ' + e.toString());
print('請求異常 url: ' + url);
}
return new ResultData(Code.errorHandleFunction(errorResponse.statusCode, e.message, noTip), false, errorResponse.statusCode);
}
try {
if (option.contentType != null && option.contentType.primaryType == "text") {
return new ResultData(response.data, true, Code.SUCCESS);
} else {
var responseJson = response.data;
if (response.statusCode == 201 && responseJson["token"] != null) {
optionParams["authorizationCode"] = 'token ' + responseJson["token"];
await SpUtils.save(Config.TOKEN_KEY, optionParams["authorizationCode"]);
}
}
if (response.statusCode == 200 || response.statusCode == 201) {
return ResultData(response.data, true, Code.SUCCESS, headers: response.headers);
}
} catch (e) {
print(e.toString() + url);
return ResultData(response.data, false, response.statusCode, headers: response.headers);
}
return new ResultData(Code.errorHandleFunction(response.statusCode, "", noTip), false, response.statusCode);
}
///清除授權(quán)
static clearAuthorization() {
optionParams["authorizationCode"] = null;
SpUtils.remove(Config.TOKEN_KEY);
}
///獲取授權(quán)token
static getAuthorization() async {
String token = await SpUtils.get(Config.TOKEN_KEY);
if (token == null) {
String basic = await SpUtils.get(Config.USER_BASIC_CODE);
if (basic == null) {
//提示輸入賬號密碼
} else {
//通過 basic 去獲取token,獲取到設(shè)置,返回token
return "Basic $basic";
}
} else {
optionParams["authorizationCode"] = token;
return token;
}
}
}
使用示例
/// 登錄 model
class LoginModel{
// 手機(jī)號碼登錄
static phoneLogin(String phone,String verifyCode) async{
ResultData response = await HttpRequest.post(Address.phoneLogin, {"phoneNum" : phone,"captcha":verifyCode});
if(response != null && response.result){
PhoneLoginEntity phoneLoginEntity = PhoneLoginEntity.fromJson(json.decode(response.data));
return new DataResult(phoneLoginEntity, true);
}else{
return new DataResult(null, false);
}
}
// 獲取驗(yàn)證碼
static getVerifyCode(String phone) async{
ResultData response = await HttpRequest.get("${Address.getVerifyCode}?phone=${phone}", null);
// var response = await HttpRequest.get(Address.getVerifyCode, {"phone":phone});
if(response != null && response.result){
VerifyCodeEntity entity = VerifyCodeEntity.fromJson(response.data);
return new DataResult(entity, true);
}else{
return new DataResult(null, false);
}
}
}