iOS应用开发中AFNetworking库的常用HTTP操作方法小结

准备
首先，你需要将AFNetworking 框架包含到工程中。如果你还没有AFNetworking的话，在这里下载最新的版本：
https://github.com/AFNetworking/AFNetworking
当你解压出下载的文件后，你将看到其中有一个AFNetworking子文件夹，里面全是.h 和 .m 文件, 如下高亮显示的:

将AFNetworking拖拽到Xcode工程中.

当出现了添加文件的选项时，确保勾选上Copy items into destination group's folder (if needed) 和 Create groups for any added folders.
将AFNetworking添加到预编译头文件，意味着这个框架会被自动的添加到工程的所有源代码文件中。

常用方法介绍
方法一：GET 请求

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);

}];

方法二：POST 请求

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);

}];

方法三：POST Multi-Part Request

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);

}];

方法四：创建一个下载文件任务

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];

方法五：创建一个上传文件任务

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];

方法六：创建一个上传文件任务并显示进度

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];

方法七：创建一个上传数据data任务

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];

方法八：获取网络状态

[[AFNetworkReachabilityManager sharedManager] setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {

    NSLog(@"Reachability: %@", AFStringFromNetworkReachabilityStatus(status));

}]; 

方法九： HTTP Manager Reachability

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;

    }

}];
[manager.reachabilityManager startMonitoring];

方法十：AFHTTPRequestOperation的GET请求

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];  

方法十一：Batch of Operations

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];

方法十二：获取请求的一些信息(我也没有用过，不太常用)

Request Serialization

Request serializers create requests from URL strings, encoding parameters as either a query string or HTTP body.
NSString *URLString = @"http://example.com";

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

Query String Parameter Encoding
[[AFHTTPRequestSerializer serializer] requestWithMethod:@"GET" URLString:URLString parameters:parameters error:nil];
GET http://example.com?foo=bar&baz[]=1&baz[]=2&baz[]=3

URL Form Parameter Encoding
[[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

JSON Parameter Encoding
[[AFJSONRequestSerializer serializer] requestWithMethod:@"POST" URLString:URLString parameters:parameters];
POST http://example.com/

Content-Type: application/json
{"foo": "bar", "baz": [1,2,3]}