title: iOS no communication between iPhone app and MySQL database via PHP
body: <p>I need help trying to figure out why my iPhone app is not communicating with my PHP. I have a text field where the user can enter a message and there is a button that is supposed to tell the app when the text has been entered and needs to be posted to my mySQL database.  </p>
  
  <p>My PHP and iOS code are pasted below, but I also included some debugging statements here.  </p>
  
  <p>I put a break at the line <code>if([serverOutput...)</code> and at that point I get the following:</p>
  
  <pre>
  alertsuccess    UIAlertView *   0x00000000
  dataURL NSData *    0x00000000 
  messageString   __NSCFString *  0x0685e7a0 @"hi"
  serverOutput    __NSCFConstantString *  0x00b75a7c
  url NSURL * 0x06869540 @"http://www.mysite.com/connect.php?message=hi"
  </pre>
  
  <p>From the debug breakpoint, I would expect serverOutput to say "OK" but it's blank, which I believe means that it did not connect with my PHP.  Your help is appreciated on how to fix this.</p>
  
  <pre><code>&lt;?php
  // Connecting, selecting database
  $link = mysql_connect("localhost", "user", "password")
  or die('Could not connect: ' . mysql_error());
  
  mysql_select_db("mydb") or die('Could not select database');
  
  // Performing SQL query
  $query = "INSERT INTO messages (message,date) VALUES ('$_GET["message"]',NOW())";
  $result = mysql_query($query) or die('Query failed: ' . mysql_error());
  
  echo "OK";
  
  // Free resultset
  mysql_free_result($result);
  
  // Closing connection
  mysql_close($link);
  ?&gt;
  </code></pre>
  
  <p>iPhone code</p>
  
  <pre><code>- (IBAction)postmessage:(id)sender {
  
  self.message = self.messageField.text;
  NSString *messageString = self.message;
  UIAlertView *alertsuccess;
  
   //construct an URL for your script, containing the encoded text for parameter value
  NSURL* url = [NSURL URLWithString:
   [NSString stringWithFormat:
   @"http://www.mysite.com/connect.php?message=%@",messageString]];
  
  NSData *dataURL =  [NSData dataWithContentsOfURL:url];
  NSString *serverOutput = [[NSString alloc] initWithData:dataURL encoding: NSASCIIStringEncoding];
  
  if([serverOutput isEqualToString:@"OK"]) {
  
     alertsuccess = [[UIAlertView alloc] initWithTitle:@"Posted" message:@"Done"
                                                            delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];
  
  } else {
      alertsuccess = [[UIAlertView alloc] initWithTitle:@"Error" message:@"Done"
                                                            delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];
  
  }
  [alertsuccess show];
  
  }
  </code></pre>