title: Concatenate NSStrings from NSMutableArray to NSString
body: <p>I need to create a <code>NSString</code> for browsing folders in FTP share. i show the directory on a TableView, and user´s can browse by selecting row ´s</p>
  
  <p>Im writing the string of selected rows into a mutable array, and then i need to make a string of all strings in the mutable array. means add the last string to the previous when the row is selected</p>
  
  <p>for example first string in array is "Downloads" second "Movies" third "HD-Movies"....... and so on
  for that i need the string on the first time selected row "/Downloads/"
  the second time "/Downloads/Movies/", an the third "/Downloads/Movies/HD-Movies"</p>
  
  <p>i´m sure i need a <code>NSMutableString</code>, but don´t know how to add the strings...</p>
  
  <p>here a part of my code:</p>
  
  <pre><code>- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
  {
  
  NSMutableArray *filePathArray = [[NSMutableArray alloc]init];
  [filePathArray addObject:@"/Downloads/"];
  [filePathArray addObject:[fileNameArray objectAtIndex:indexPath.row]];
  
  }
  </code></pre>