iOS 8 Simulator中的writeToFile

Question

I'm trying to write a simple string to file, using the following code:

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

    NSString *fileName = [NSString stringWithFormat:@"%@/textfile.txt",
                          documentsDirectory];
    NSString *content = @"Test Content";
    NSError *error = nil;
    [content writeToFile:fileName atomically:NO encoding:NSStringEncodingConversionAllowLossy error:&error];

    NSLog(@"Error %@ %@", fileName, error);

But the file is'nt written and error is null.

I'm running the code in the iOS Simulator and expect the file to be written to a location like: /Users/user/Library/Developer/CoreSimulator/Devices/85DDC17D-A771-40D9-99BE-71FF6B60D2DF/data/Containers/Data/Application/BD30A945-25DB-4ECE-B7F7-E9C20C6691C7/Documents/textfile.txt (the Path of fileName from NSLog).

Answer 1

As @rckoenes pointed out it was an error in the rest of my code. I have a function that deletes all files in "documents", i just didn't remember that i had this function and because of the length of the code (>5000 lines) it was hard to find. Thank you all!

Answer 2

working with URLs is a bit reliable way, so I would re-work your idea slightly like eg this:

NSURL *_documentFolder = [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
NSURL *_fileURL = [_documentFolder URLByAppendingPathComponent:@"textFile.txt"];
NSError *_error = nil;
BOOL _success = [@"hello!" writeToURL:_fileURL atomically:TRUE encoding:NSUTF8StringEncoding error:&_error];

that works perfectly on simulator and on real device too, and the file textFile.txt will have the content hello! .

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NOTE: if the _success value is FALSE , you can get more information about the reason via a the _error , even if you'd just log it to the debug-console. I have not isolated the NSString in my example, but you can replace it with your own instance.

Answer 3

please check below code:

   NSArray *paths = NSSearchPathForDirectoriesInDomains( NSDocumentDirectory, NSUserDomainMask, YES);
   NSString *filePath = [[pathsobjectAtIndex:0]stringByAppendingPathComponent:@"textfile.txt"];
   NSString *temp = [[NSString alloc] initWithString:@"Test Content"];
   [temp writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:nil];