iPhone - NSData from local file's URL

88
votes

I have a NSURL object which gives me the path of a local file (in documents folder). I want to populate an NSData object with the contents of this file. Tried using dataWithContentsOfURL: but this fails. I know the file exists because the iPhone SDK returns the path.

Can someone please tell me how I can get an NSData object from the URL of a local file?

Thanks.

5
iphonensdatansurl
What does "but it fails" mean? - Marco
Means it freezes at this point! Gives an exception. I am trying to access a video's data, the URL of which we get from UIImagePickerController - lostInTransit
Seems you're trying to pass an object that is not a NURL. How are you getting the file URL, are you sure is an URL and not a NSString? - Marco
@AliKhaki: Please don't make trivial edits, it takes two people in the review queue to look over your changes. If you edit a question to improve it, feel free to remove useless stuff like "thanks", but don't edit the question just for that. Thanks! - Cris Luengo

5 Answers

170
votes
// Given some file path URL: NSURL *pathURL
// Note: [pathURL isFileURL] must return YES
NSString *path = [pathURL path];
NSData *data = [[NSFileManager defaultManager] contentsAtPath:path];

Swift code:

let data = FileManager.default.contents(atPath: path)
29
votes

To get this work you just need to do:

NSURL *imgPath = [[NSBundle mainBundle] URLForResource:@"search" withExtension:@"png"];
NSString*stringPath = [imgPath absoluteString]; //this is correct  

//you can again use it in NSURL eg if you have async loading images and your mechanism 
//uses only url like mine (but sometimes i need local files to load)
NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:stringPath]];
UIImage *ready = [[[UIImage alloc] initWithData:data] autorelease];
2
votes

Make sure your local URL starts with "file://" then you would just have to do this:

 NSData *fileData = [NSData dataWithContentsOfFile:fileURL.path];
0
votes

For swift3 I found answer from following URL helpful

( I was getting following path , after capturing image using phonegap plugin

file:///var/mobile/Containers/Data/Application/B64B06DE-7976-45CF-9BE2-661F0F309A06/tmp/abcded.jpg )

https://stackoverflow.com/a/41043447/6383908

if let videoURL = URL(string: urlString), let videodata = try? Data(contentsOf: videoURL) { //Add code of Alamofire here }

0
votes
guard let data = FileManager.default.contents(atPath: path) else
    { ...