Question

I am reading a file in iphone app. Its Works Fine.

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSLog(@"%@",documentsDirectory);
    NSString *fileName = [NSString stringWithFormat:@"%@/test.txt",documentsDirectory];
    NSLog(@"%@",fileName);
    NSString *content = [[NSString alloc] initWithContentsOfFile:fileName
                                                    usedEncoding:nil
                                                           error:nil];
    NSLog (@"%@",content);
}

works good when i am using filename as test.txt

But when i add another file in the resource suppose test1.txt then NSLog(@"%@",documentsDirectory) and NSLog(@"%@",fileName) shows the right result. But

NSLog (@"%@",content); prints null in the log. So what is the reason?

I am printing detail error and it prints

NSFilePath = "/Users/sam-xxx/Library/Application Support/iPhone Simulator/3.2/Applications/51197946-6042-4A90-AA39-F07F8A649308/Documents/test1.txt";
    NSUnderlyingError = Error Domain=NSPOSIXErrorDomain Code=2 "Operation could not be completed. No such file or directory";

Answer 1

It would be best here to check to see if an error is returned:

NSError *error;
NSString *content = [[NSString alloc] initWithContentsOfFile:fileName
                                                usedEncoding:nil
                                                       error: &error];
if (error) NSLog(@"Error !: %@", [error localizedDescription]);

That will (hopefully) give you a clue as to whats going on.

(Edited to give example bundle resource usage as the file is in the bundle not the Documents directory).

Docs for NSBundle are here: NSBundle Documentation

You have 2 choices, the one you suggest:

NSString *databasePathFromApp = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:fileName];

Which will return the Bundle resource directory with the filename appended to that path.

Personally I prefer the pathForResource:ofType: method:

NSString *filename = [[NSBundle mainBundle] pathForResource: @"test1" ofType: @"txt"];

As this will not only tell you if the file exists (returns nil if it does not) but will also search the localisation directories if you have them.