iOS 从 iCloud Drive 下载文件

Question

在我的 iOS 应用程序中，我将一些文件存储到 iCloud Drive 文件夹以进行备份。现在我想检索该文件，但我不知道这样做的正确方法是什么。我的意思是如果 iCloud Drive 有任何特定的方法，或者我可以从 url 中获取它。

我像这样将文件存储到 iCLoud ( https://stackoverflow.com/a/27358392/3065901 ):

- (void) storeToIcloud
{
   // Let's get the root directory for storing the file on iCloud Drive
   [self rootDirectoryForICloud:^(NSURL *ubiquityURL) {

        if (ubiquityURL) {

             // We also need the 'local' URL to the file we want to store

             NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
             NSString *documentsPath = [paths objectAtIndex:0]; //Get the docs directory
             NSString *filePath = [documentsPath stringByAppendingPathComponent:@"myFile.xml"]; //Add the file name

             NSURL *localURL = [NSURL fileURLWithPath:filePath];

             // Now, append the local filename to the ubiquityURL
             ubiquityURL = [ubiquityURL URLByAppendingPathComponent:localURL.lastPathComponent];

             // And finish up the 'store' action
             NSError *error;
             if (![[NSFileManager defaultManager] setUbiquitous:YES itemAtURL:localURL destinationURL:ubiquityURL error:&error]) {
                NSLog(@"Error occurred: %@", error);
             }
        }
        else {
            NSLog(@"Could not retrieve a ubiquityURL");
        }
   }];
}

- (void)rootDirectoryForICloud:(void (^)(NSURL *))completionHandler {

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
        NSURL *rootDirectory = [[[NSFileManager defaultManager] URLForUbiquityContainerIdentifier:nil]URLByAppendingPathComponent:@"Documents"];

        if (rootDirectory) {
             if (![[NSFileManager defaultManager] fileExistsAtPath:rootDirectory.path isDirectory:nil]) {
                  NSLog(@"Create directory");
                  [[NSFileManager defaultManager] createDirectoryAtURL:rootDirectory withIntermediateDirectories:YES attributes:nil error:nil];
             }
        }

        dispatch_async(dispatch_get_main_queue(), ^{
             completionHandler(rootDirectory);
        });
    });
}

- (NSURL *)localPathForResource:(NSString *)resource ofType:(NSString *)type {
      NSString *documentsDirectory = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0];
      NSString *resourcePath = [[documentsDirectory stringByAppendingPathComponent:resource] stringByAppendingPathExtension:type];
      return [NSURL fileURLWithPath:resourcePath];
}

如何从 iCloud 驱动器下载文件？

提前致谢。

Answer 1

你应该使用 NSMetadataQuery 从 icloud 获取项目，然后当你将书签挂接到文件时使用 NSFileCoordination 读取它，可以使用相同的方法从云端或您的应用程序沙盒中读取...此处详细解释了所有内容:Building Document Based Apps ，甚至还有一些您可以遵循的示例代码。希望这对您有所帮助!