title: Check if file name exists in document directory
body: <p>In my application I am using the following code to save images/files into the application’s document directory:</p>
  
  <pre><code>-(void)saveImageDetailsToAppBundle{
      NSData *imageData = UIImagePNGRepresentation(userSavedImage); //convert image into .png format.
      NSFileManager *fileManager = [NSFileManager defaultManager];//create instance of NSFileManager
      NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); //create an array and store result of our search for the documents directory in it
      NSString *documentsDirectory = [paths objectAtIndex:0]; //create NSString object, that holds our exact path to the documents directory
      NSString *fullPath = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.png",txtImageName.text]]; //add our image to the path
  
      NSLog(fullPath);
  
      [fileManager createFileAtPath:fullPath contents:imageData attributes:nil]; //finally save the image
  
      NSLog(@"image saved"); 
  }
  </code></pre>
  
  <p>However, there is a problem with the image name. If a file exists in the documents directory, the new file with the same name will overwrite the old file. How can I check if the file name exists in the documents directory?</p>