IOS網絡訪問之使用AFNetworking

AFNetworking是IOS上常用的第三方網絡訪問庫，我們可以在github上下載它，同時github上有它詳細的使用說明，最新的AFNetworing2.0與1.0有很大的變化，這里僅對2.0常用的使用方法進行總結

基於NSURLConnection的API

提交GET請求

AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
[manager GET:@"http://example.com/resources.json" parameters:nil success:^(AFHTTPRequestOperation *operation, id responseObject) {
　　  NSLog(@"JSON: %@", responseObject);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
　　  NSLog(@"Error: %@", error);
}];

AFResponseSerializer

上面代碼中responseObject代表了返回的值，當網絡返回json或者xml之類的數據時，它們的本質都是字符串，我們需要通過一定操作才能把字符串轉成希望的對象，AFNetWorking通過設置AFHTTPRequestOperationManager對象的responseSerializer屬性替我們做了這些事。

如果返回的數據時json格式，那么我們設定

manager.responseSerializer = [[AFJSONResponseSerializer alloc] init]，responseObject就是獲得的json的根對象（NSDictionary或者NSArray）

如果返回的是plist格式我們就用AFPropertyListResponseSerializer解析器

如果返回的是xml格式我們就用AFXMLParserResponseSerializer解析器，responseObject代表了NSXMLParser對像

如果返回的是圖片，可以使用AFImageResponseSerializer

如果只是希望獲得返回二進制格式，那么可以使用AFHTTPResponseSerializer

AFRequestSerializer 

AFHTTPRequestOperationManager還可以通過設置requestSeializer屬性設置請求的格式

有如下的請求地址與參數

NSString *URLString = @"http://example.com";

NSDictionary *parameters = @{@"foo": @"bar", @"baz": @[@1, @2, @3]};

 

我們使用AFHTTPRequestSerializer的GET提交方式

[[AFHTTPRequestSerializer serializer] requestWithMethod:@"GET" URLString:URLString parameters:parameters error:nil];

GET http://example.com?foo=bar&baz[]=1&baz[]=2&baz[]=3

 

我們使用AFHTTPRequestSerializer的POST提交方式

[[AFHTTPRequestSerializer serializer] requestWithMethod:@"POST" URLString:URLString parameters:parameters];

POST http://example.com/

Content-Type: application/x-www-form-urlencoded

foo=bar&baz[]=1&baz[]=2&baz[]=3

 

我們使用AFJSONRequestSerializer

[[AFJSONRequestSerializer serializer] requestWithMethod:@"POST" URLString:URLString parameters:parameters];

POST http://example.com/

Content-Type: application/json

{"foo": "bar", "baz": [1,2,3]}

 

默認提交請求的數據是二進制（AFHTTPRequestSerializer）的,返回格式是JSON（AFJSONResponseSerializer）

 

提交POST請求

AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
NSDictionary *parameters = @{@"foo": @"bar"};
[manager POST:@"http://example.com/resources.json" parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject) {
    NSLog(@"JSON: %@", responseObject);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
    NSLog(@"Error: %@", error);
}];

 

提交POST請求時附帶文件

AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
NSDictionary *parameters = @{@"foo": @"bar"};
NSURL *filePath = [NSURL fileURLWithPath:@"file://path/to/image.png"];
[manager POST:@"http://example.com/resources.json" parameters:parameters constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
    [formData appendPartWithFileURL:filePath name:@"image" error:nil];
} success:^(AFHTTPRequestOperation *operation, id responseObject) {
    NSLog(@"Success: %@", responseObject);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
    NSLog(@"Error: %@", error);
}];

也可以通過appendPartWithFileData上傳NSData數據的文件

 

AFHTTPRequestOperation

除了使用AFHTTPRequestOperationManager訪問網絡外還可以通過AFHTTPRequestOperation，AFHTTPRequestOperation繼承自AFURLConnectionOperation，

AFURLConnectionOperation繼承自NSOperation，所以可以通過AFHTTPRequestOperation定義了一個網絡請求任務，然后添加到隊列中執行。

NSURL *URL = [NSURL URLWithString:@"http://example.com/resources/123.json"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL]; AFHTTPRequestOperation *op = [[AFHTTPRequestOperation alloc] initWithRequest:request]; op.responseSerializer = [AFJSONResponseSerializer serializer]; [op setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) { NSLog(@"JSON: %@", responseObject); } failure:^(AFHTTPRequestOperation *operation, NSError *error) { NSLog(@"Error: %@", error); }]; [[NSOperationQueue mainQueue] addOperation:op];

 批量任務處理

NSMutableArray *mutableOperations = [NSMutableArray array];
for (NSURL *fileURL in filesToUpload) { NSURLRequest *request = [[AFHTTPRequestSerializer serializer] multipartFormRequestWithMethod:@"POST" URLString:@"http://example.com/upload" parameters:nil constructingBodyWithBlock:^(id<AFMultipartFormData> formData) { [formData appendPartWithFileURL:fileURL name:@"images[]" error:nil]; }]; AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request]; [mutableOperations addObject:operation]; } NSArray *operations = [AFURLConnectionOperation batchOfRequestOperations:@[...] progressBlock:^(NSUInteger numberOfFinishedOperations, NSUInteger totalNumberOfOperations) { NSLog(@"%lu of %lu complete", numberOfFinishedOperations, totalNumberOfOperations); } completionBlock:^(NSArray *operations) { NSLog(@"All operations in batch complete"); }]; [[NSOperationQueue mainQueue] addOperations:operations waitUntilFinished:NO];

 

上面的API是基於NSURLConnection，IOS7之后AFNetWorking還提供了基於NSURLSession的API

基於NSURLSession的API

下載任務

NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];

NSURL *URL = [NSURL URLWithString:@"http://example.com/download.zip"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];

NSURLSessionDownloadTask *downloadTask = [manager downloadTaskWithRequest:request progress:nil destination:^NSURL *(NSURL *targetPath, NSURLResponse *response) {
    NSURL *documentsDirectoryURL = [[NSFileManager defaultManager] URLForDirectory:NSDocumentDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:NO error:nil];
    return [documentsDirectoryURL URLByAppendingPathComponent:[response suggestedFilename]];
} completionHandler:^(NSURLResponse *response, NSURL *filePath, NSError *error) {
    NSLog(@"File downloaded to: %@", filePath);
}];
[downloadTask resume];

 

文件上傳任務

NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];

NSURL *URL = [NSURL URLWithString:@"http://example.com/upload"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];

NSURL *filePath = [NSURL fileURLWithPath:@"file://path/to/image.png"];
NSURLSessionUploadTask *uploadTask = [manager uploadTaskWithRequest:request fromFile:filePath progress:nil completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
    if (error) {
        NSLog(@"Error: %@", error);
    } else {
        NSLog(@"Success: %@ %@", response, responseObject);
    }
}];
[uploadTask resume];

 

帶進度的文件上傳

NSMutableURLRequest *request = [[AFHTTPRequestSerializer serializer] multipartFormRequestWithMethod:@"POST" URLString:@"http://example.com/upload" parameters:nil constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
        [formData appendPartWithFileURL:[NSURL fileURLWithPath:@"file://path/to/image.jpg"] name:@"file" fileName:@"filename.jpg" mimeType:@"image/jpeg" error:nil];
    } error:nil];

AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration]];
NSProgress *progress = nil;

NSURLSessionUploadTask *uploadTask = [manager uploadTaskWithStreamedRequest:request progress:&progress completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
    if (error) {
        NSLog(@"Error: %@", error);
    } else {
        NSLog(@"%@ %@", response, responseObject);
    }
}];

[uploadTask resume];

 

NSURLSessionDataTask

NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];

NSURL *URL = [NSURL URLWithString:@"http://example.com/upload"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];

NSURLSessionDataTask *dataTask = [manager dataTaskWithRequest:request completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
    if (error) {
        NSLog(@"Error: %@", error);
    } else {
        NSLog(@"%@ %@", response, responseObject);
    }
}];
[dataTask resume];

 

查看網絡狀態

蘋果官方提供Reachablity用來查看網絡狀態，AFNetWorking也提供這方面的API

NSURL *baseURL = [NSURL URLWithString:@"http://example.com/"];
AFHTTPRequestOperationManager *manager = [[AFHTTPRequestOperationManager alloc] initWithBaseURL:baseURL];

NSOperationQueue *operationQueue = manager.operationQueue;
[manager.reachabilityManager setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {
    switch (status) {
        case AFNetworkReachabilityStatusReachableViaWWAN:
        case AFNetworkReachabilityStatusReachableViaWiFi:
            [operationQueue setSuspended:NO];
            break;
        case AFNetworkReachabilityStatusNotReachable:
        default:
            [operationQueue setSuspended:YES];
            break;
    }
}];

//開始監控
[manager.reachabilityManager startMonitoring];