Question

我正在尝试下载文本文件，如果暂停此下载，我会尝试附加文件的其余部分。

问题是我开始从正确的位置下载其余的但是文件没有附加它会覆盖以前的文件。

这是我的源代码： +（void）downloadFile：（NSManagedObject *）file {

NSString *url = [file valueForKey:@"path"];

NSString *fileName = [[file valueForKey:@"path"] lastPathComponent]; // TODO chnage to file ID (it will be good to add id before file name)

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:fileName];

NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:url]];

BOOL append = NO;
unsigned long long size = 0;
BOOL resumeOperation = NO;
if ([[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
    resumeOperation = YES;
    NSError *error = nil;
    NSDictionary *dict = [[NSFileManager defaultManager] attributesOfItemAtPath:filePath error:&error];
    size = [[dict objectForKey:NSFileSize] longLongValue];

    if (!error) {
        error = nil;
        [[NSFileManager defaultManager] removeItemAtPath:filePath error:&error];

        if (error) {
            NSLog(@"Error removing old file: %@", [error localizedDescription]);
        }

        NSString *val = [NSString stringWithFormat:@"bytes=%lld-", size];
        append = YES;
        [request setValue:val forHTTPHeaderField:@"Range"];
    }

}

AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request] ;


operation.outputStream = [NSOutputStream outputStreamToFileAtPath:filePath append:YES];


//gives more 10 minuts when the app is minimmized
[operation setShouldExecuteAsBackgroundTaskWithExpirationHandler:^{
    [operation pause];
}];

[operation setDownloadProgressBlock:^(NSUInteger bytesRead, long long totalBytesRead, long long totalBytesExpectedToRead) {
    totalBytesRead += size;
    float percent = ((float)totalBytesRead) / (totalBytesExpectedToRead + size);

 //        TODO update database with bytes amount
       NSLog(@"%.2f%% - [%d]", percent * 100, [[CoreDataManager getQueue] count]);
    }];

    [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id      responseObject) {
    NSLog(@"File downloaded succesffully!");
    [self reportEndDownload:file withStatusCode:[NSNumber numberWithInt:DOWNLAOD_STATUS_COMPLETE]];
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
//        NSLog(@"Error while downloading file: %@", [error localizedDescription]);
//        ? ask about server corrupted files - here is a loop -----> Itay OK
    [self reportEndDownload:file withStatusCode:[NSNumber numberWithInt:DOWNLOAF_STATUS_CONNECTION_ERROR]];
}];

 if (resumeOperation ) {
     [operation resume];
 }else{
     [operation start];
 }


}

Answer 1

您可以使用AFDownloadRequestOperation执行此操作。

NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"....zip"]];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *path = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"....zip"];
AFDownloadRequestOperation *operation = [[AFDownloadRequestOperation alloc] initWithRequest:request targetPath:path shouldResume:YES];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
    NSLog(@"Successfully downloaded file to %@", path);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
    NSLog(@"Error: %@", error);
}];
[operation setProgressiveDownloadProgressBlock:^(NSInteger bytesRead, long long totalBytesRead, long long totalBytesExpected, long long totalBytesReadForFile, long long totalBytesExpectedToReadForFile) {
    NSLog(@"Operation%i: bytesRead: %d", 1, bytesRead);
    NSLog(@"Operation%i: totalBytesRead: %lld", 1, totalBytesRead);
    NSLog(@"Operation%i: totalBytesExpected: %lld", 1, totalBytesExpected);
    NSLog(@"Operation%i: totalBytesReadForFile: %lld", 1, totalBytesReadForFile);
    NSLog(@"Operation%i: totalBytesExpectedToReadForFile: %lld", 1, totalBytesExpectedToReadForFile);
}];
[operations addObject:operation];

使用append：YES with operation.outputStream AFHTTPRequestOperation不起作用

1 个答案: