i am using NSURLConnection to download file from server and storing it locally as follows
-(void) connection:(NSURLConnection *)connection
didReceiveData:(NSData *)data
{
[webData appendData:data];
paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory , NSUserDomainMask, YES);
self.documentsDir = [[paths objectAtIndex:0]stringByAppendingPathComponent:#"NewResult.zip" ];
[[NSFileManager defaultManager] createFileAtPath:documentsDir contents:nil attributes:nil];
NSFileHandle *file1 = [NSFileHandle fileHandleForUpdatingAtPath: documentsDir];
[file1 writeData: webData];
[file1 closeFile];
}
this is working but overwrite old file every time
how to avoid this over writing I know this is possible with NSURLDownload but here i am not using NSURLDownload.
if (![fileManager fileExistsAtPath: path]){
NSLog(#"File not exists at path %#", path);
}else{
NSLog(#"File exists at path:%#", path);
}
Related
I am using the following line of code to save my file of yoyo.txt in the Documents folder ::
NSString *docDir = [NSHomeDirectory() stringByAppendingPathComponent:#"Documents"];
NSLog(#"docDir is yoyo :: %#", docDir);
NSString *FilePath = [docDir stringByAppendingPathComponent:#"yoyo.txt"];
However, I wish to save my file in a folder of yoyo i.e. inside the Documents folder i.e. I want to create another folder named as "yoyo" and then save my file of yoyo.txt into it. How can I do that ?? Thanks.
Here is a sample code (assume manager is [NSFileManager defaultManager]):
BOOL isDirectory;
NSString *yoyoDir = [docDir stringByAppendingPathComponent:#"yoyo"];
if (![manager fileExistsAtPath:yoyoDir isDirectory:&isDirectory] || !isDirectory) {
NSError *error = nil;
NSDictionary *attr = [NSDictionary dictionaryWithObject:NSFileProtectionComplete
forKey:NSFileProtectionKey];
[manager createDirectoryAtPath:yoyoDir
withIntermediateDirectories:YES
attributes:attr
error:&error];
if (error)
NSLog(#"Error creating directory path: %#", [error localizedDescription]);
}
+(void)createDirForImage :(NSString *)dirName
{
NSString *path;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
path = [[paths objectAtIndex:0] stringByAppendingPathComponent:dirName];
NSError *error;
if (![[NSFileManager defaultManager] fileExistsAtPath:path]) //Does directory already exist?
{
if (![[NSFileManager defaultManager] createDirectoryAtPath:path
withIntermediateDirectories:NO
attributes:nil
error:&error])
{
NSLog(#"Create directory error: %#", error);
}
}
}
Here dataPath will be the final path for saving your file
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0]; // Get documents folder
NSString *dataPath = [documentsDirectory stringByAppendingPathComponent:#"/yoyo"];
if (![[NSFileManager defaultManager] fileExistsAtPath:dataPath]){
[[NSFileManager defaultManager] createDirectoryAtPath:dataPath withIntermediateDirectories:NO attributes:nil error:&error]; //Create folder
}
dataPath = [dataPath stringByAppendingPathComponent:#"/yoyo.txt"];
I'm downloading pdf documents from the server:
- (void)downloadSingleDocument:(NSURL *)url
{
[pdfData release];
pdfData = [[NSMutableData alloc] init];
NSMutableURLRequest *req = [NSMutableURLRequest requestWithURL:url];
[req addValue:#"Basic **************=" forHTTPHeaderField:#"Authorization"];
downloadConnection = [[NSURLConnection alloc] initWithRequest:req delegate:self startImmediately:YES];
}
- (void)connection:(NSURLConnection *)conn didReceiveData:(NSData *)data
{
NSLog(#"Connection did receive data");
[pdfData appendData:data];
}
On connectionDidFinishLoading I want to save downloaded pdf file to filesystem in Documents directory with the same filename as it was on the server.
What is the best way to do it?
Use this methods if you have large file:
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse*)response
{
filepath = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0] stringByAppendingPathComponent:save_name];
[[NSFileManager defaultManager] createFileAtPath:filepath contents:nil attributes:nil];
file = [[NSFileHandle fileHandleForUpdatingAtPath:filepath] retain];// Here file is object of NSFileHandle and its declare in .h File
[file seekToEndOfFile];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
[file seekToEndOfFile];
[file writeData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection*)connection
{
[file closeFile];
// After you download your data. you can copy your data from here to filesystem. and remove from here
}
Use NSURLDownload.
Sorry, that is only available on the Mac, not for iOS.
Create a temporary file, and append the received data to it in connection:didReceiveData:. In connectionDidFinishLoading:, move the file to the correct place, and in connection:didFailWithError:, remove the temporary file.
This should do it
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
NSString *documentsDirectory = [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
NSString *filename = [con.originalRequest.URL lastPathComponent];
NSString *path = [documentsDirectory stringByAppendingString:filename];
NSFileManager *fileManager = [NSFileManager defaultManager];
[fileManager createFileAtPath:path contents:pdfData attributes:nil];
}
I downloaed the file using code shown below. Then i am trying to save NSMutableData variable to file, however, the file is not created. What am i doing wrong? Do i need to convert NSMutableData into NSString?
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)_response {
response = [_response retain];
if([response expectedContentLength] < 1) {
data = [[NSMutableData alloc] init];
}
else {
data = [[NSMutableData dataWithCapacity:[response expectedContentLength]] retain];
}
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)_data {
[data appendData:_data];
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
NSString *filePath = [[NSBundle mainBundle] pathForResource:#"file" ofType:#"txt"];
NSLog(#"saved: %#", filePath);
[data writeToFile:filePath atomically:YES];
NSLog(#"downloaded file: %#", data); //all i see in log is some encoded data here
}
You can’t write inside your app’s bundle. You’ll need to save it somewhere else, like your app’s Documents directory:
NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *filePath = [documentsPath stringByAppendingPathComponent:#"file.txt"];
[data writeToFile:filePath atomically:YES];
Hi i want to show the received bytes in the console.
(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[receivedData appendData:data];
NSNumber *resourceLength = [NSNumber numberWithUnsignedInteger:[receivedData length]];
NSLog(#"resourceData length: %d ", [resourceLength intValue]);
if (file) {
[file seekToEndOfFile];
}
[file writeData:data];
}
the file successfully downloads and safed it into docoument dir but the nslog show always
resourceData length: 0
receivedata is NSMutableData *receivedData; in the .h file
the strange thing is that the exceptedbytes work well. here the code for that:
- (void)connection:(NSURLConnection )connection didReceiveResponse:(NSURLResponse)response {
localFilename = [[[url2 absoluteString] lastPathComponent] copy];
NSLog(localFilename);
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0] ;
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:localFilename];
[[NSFileManager defaultManager] createFileAtPath:appFile contents:nil attributes:nil];
expectedBytes = [response expectedContentLength];
NSLog(#"content-length: %lli Bytes", expectedBytes);
file = [[NSFileHandle fileHandleForUpdatingAtPath:appFile] retain];
if (file) {
[file seekToEndOfFile];
}
}
can somebody help me. i really dont know what i am doing wrong
kind regards
tammo
Have you allocated and initialised receivedData? One usually does
receivedData = [[NSMutableData data] retain];
right after creating an NSURLConnection instance, and then
[receivedData setLength:0];
upon receiving a response via -connection:didReceiveResponse:, and
[receivedData appendData:data];
upon receiving data via -connection:didReceiveData:. This is exemplified in the URL Loading System Programming Guide. If you haven’t instantiated receivedData, it is probably nil and [receivedData length] returns 0 in that case.
I'm using the NSURLConnection class to download a large file in my iPhone application, but it crashes every so often because it's using too much memory. I'm doing the usual NSURLConnection usage, to append the received data to a NSMutableData object.
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[self.fileData appendData:data];
}
Then after I finish downloading the whole file, I save it to a local temporary file, and read it as a mapped file like this:
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
// save the downloaded data into a temporary file
NSString *tempPath = NSTemporaryDirectory();
NSString *tempFile = [tempPath stringByAppendingPathComponent:#"temp.pdf"];
[self.fileData writeToFile:tempFile atomically:YES];
NSData *mappedData = [NSData dataWithContentsOfMappedFile:tempFile];
NSURL *baseURL = [NSURL URLWithString:#"http://mydomain.com"];
[webView loadData:mappedData MIMEType:#"application/pdf" textEncodingName:#"UTF-8" baseURL:baseURL];
}
What can I improve here to avoid these memory usage problems?
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse*)response {
filename = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0] stringByAppendingPathComponent:save_name]; // filename is in .h file
[[NSFileManager defaultManager] createFileAtPath:filename contents:nil attributes:nil];
file =
[[NSFileHandle fileHandleForUpdatingAtPath:filename] retain];// file is in .h
//if (file) {
//
// [file seekToEndOfFile];
// }
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSD
ata *)data {
if (file) {
[file seekToEndOfFile];
} [file writeData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection*)connection {
[file closeFile];
}
If it's that large, why not write it to the file as it comes in, rather than keeping it in an NSData object?
i'm using
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
filename = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0] stringByAppendingPathComponent:save_name];
NSFileHandle *file1 = [NSFileHandle fileHandleForUpdatingAtPath: filename];
[file1 writeData: data];
[file1 closeFile];
}