从UIImagePickerController向服务器发送UIImage POST

Question

我正试图将带有UIImagePickerController的UIImage take与其他相关值一起发送到服务器POST。但我看到了试图将字典值@"image"设置为UIImageJPEGRepresentation（image，1.0）的行：

-(void)sendImageToServer:(UIImage *)image
{
    NSOperationQueue *queue = [[NSOperationQueue alloc] init];
    queue.maxConcurrentOperationCount = 4;
    NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration ephemeralSessionConfiguration] delegate:nil delegateQueue:queue];
    NSURL *uploadURL = [NSURL URLWithString:@"http://...."];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:uploadURL cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:30.0];
    [request addValue:@"application/json" forHTTPHeaderField:@"Accept"];
    [request setHTTPMethod:@"POST"];
    NSData *postData = [[NSData alloc] init];
    [postData setValue:UIImageJPEGRepresentation(image, 1.0) forKey:@"image"];
    [postData setValue:@"1" forKey:@"categories[0]"];
    [postData setValue:@"4" forKey:@"categories[1]"];
    NSURLSessionUploadTask *uploadTask = [session uploadTaskWithRequest:request
                                                               fromData:postData
                                                      completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
        if (!error) {
            NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)response;
            if (httpResponse.statusCode == 200) {
                dispatch_async(dispatch_get_main_queue(), ^{
                    NSError *err;
                    NSDictionary *JSONDict = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&err];
                    NSLog(@"HTTP 200 response: %@", JSONDict);
                });
            } else {    
                NSLog(@"HTTP %ld status!", (long)httpResponse.statusCode);
            }   
        } else {
            NSLog(@"HTTP post image error: %@", error);
        }
    }];
    [uploadTask resume];
}

JSON序列化在这里不起作用，因为图像不是有效的JSON值。如果另一方面我尝试：

...
NSMutableData *postData = [[NSMutableData alloc] init];
    NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:postData];
    [archiver encodeObject:UIImageJPEGRepresentation(image, 1.0) forKey:@"image"];
    [archiver encodeObject:@"1" forKey:@"categories[0]"];
    [archiver encodeObject:@"4" forKey:@"categories[1]"];
    [archiver finishEncoding];

    //NSData *postData = [NSJSONSerialization dataWithJSONObject:dataDict options:NSJSONWritingPrettyPrinted error:&jsonError];
    //Now you can post the json data
    NSURLSessionUploadTask *uploadTask = [session uploadTaskWithRequest:request
                                                               fromData:postData
                                                      completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {...

存档的密钥：值对似乎并没有像这样到达服务器。这必须是iOS的常规编码任务。

即使我只是尝试：

NSError *jsonError;
    NSData *postData = [NSJSONSerialization dataWithJSONObject:@{@"image":@"123",@"categories[0]":@"1",@"categories[1]":@"4"} options:NSJSONWritingPrettyPrinted error:&jsonError];

服务器根本没有得到任何密钥。。。

Answer 1

这不是NSData的正确用法。它现在崩溃了，因为NSData没有密钥命名的映像（..或之后的其他两个）。您需要做的是创建一个NSDictionary，然后将其转换为NSData。

改为这样做：

NSDictionary *dictionary = [NSDictionary alloc]initWithObjectsAndKeys:image,@"image",@(1),@"categories[0]",@(4),@"categories[1]", nil];
NSData *data = [NSKeyedArchiver archivedDataWithRootObject:dictionary]; //Not currently using NSJSONSerialization since you want to post a Dictionary with an invalid NSJSONSerialization type in it.
//Now you can post the json data

Answer 2

试试AFNetworking，它有一个很好的上传方法，你可以在这里找到示例：https://github.com/AFNetworking/AFNetworking#creating-上传任务

我个人建议每个人都使用它，因为我开始使用它，所以在与网络服务器通信时没有遇到任何问题。

Answer 3

使用AFNetworking和多部分表单帖子。这里有一个粗略的例子（注意，我传递了一个块，所以您的实现会有所不同）：

AFHTTPRequestOperation *operation = [self POST:FullURLString parameters:Params constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
        [formData appendPartWithFileData:fileData name:fileName fileName:fileName mimeType:mimeType];
    } success:^(AFHTTPRequestOperation *operation, id responseObject) {
        NSData *responseData = [operation responseData];
        id retObj;
        NSError *error = nil;
        if (responseData) {
            retObj = [NSJSONSerialization JSONObjectWithData:responseData options:0 error:&error];
        }
        // Pass back the serialized object (either an NSArray of type NSDictionaries or an NSArray of type customClass)
        block(retObj);
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"Failed with error = [Error]: %@", error);
        block(nil);
}];