Check if file exists at URL instead of path

objective-c nsfilemanager
Pedro Sousa picture Pedro Sousa · Oct 24, 2011 · Viewed 27.4k times · Source

How can I check if a file exists at a URL (instead of a path), in order to set a pre-populated default store into the iPhone Simulator: 

NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"Food.sqlite"];
/*
 Set up the store.
 For the sake of illustration, provide a pre-populated default store.
 */
NSFileManager *fileManager = [NSFileManager defaultManager];
// If the expected store doesn't exist, copy the default store.
if (![fileManager fileExistsAtPath:storePath]) {
    NSString *defaultStorePath = [[NSBundle mainBundle] pathForResource:@"Food" ofType:@"sqlite"];
    if (defaultStorePath) {
        [fileManager copyItemAtPath:defaultStorePath toPath:storePath error:NULL];
    }
}

I've read that in recent versions of the templates, the applicationDocumentsDirectory method returns an URL, so I've changed the code to use NSURL objects to represent the file path. But at [fileManager fileExistsAtPath:storePath], I need to change fileExistsAtPath to something like fileExistsAtURL (obviously it doesn't exist).

I've checked the NSFileManager Class Reference and I didn't find any suitable task suited for my purpose.

Any hints please?

Answer

Mundi picture Mundi · Oct 24, 2011 
if (![fileManager fileExistsAtPath:[storeURL path]]) 
...

From the documentation:

If this URL object contains a file URL (as determined with isFileURL), the return value of this method is suitable for input into methods of NSFileManager or NSPathUtilities. If the path has a trailing slash it is stripped.

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