problem with redirect/ site design

[mattastic]

Hi,

I'm having problems with the way I redirect users, when users add an event or edit an event in my calendar.

I have it setup so my index page includes all the other pages within a div, by passing a variable to the index page, which is the name of the page to be included.

This works fine but my problem is when I add an event using a form, the form is sent to 'index.php?page=addeventaction' where I want to insert the details into the event table, and redirect them back to my default welcome page.

Obviously this wont work with the code I have below, which is my editaction page.

I keep getting this error:

Warning: Cannot modify header information - headers already sent by (output started at C:\Program Files\xampp\htdocs\index.php:3) in C:\Program Files\xampp\htdocs\addeventaction.php on line 46

Is this way possible?

If not is there any way I can use my index includes with redirects?

Thanks in advance.

 <?php 

 /* connect to db */
$link_id = db_connect();

 /* confirm form is posted */
 if (isset($_REQUEST['send']))
{


/* set posted variables */
$title = $_POST['title'];
$description = $_POST['description'];

 /* Check startdate is valid  */
if (checkdate($_POST['startmonth'],$_POST['startday'],$_POST['startyear']) != NULL)
	{
$startdate = $_POST['startyear']."-".$_POST['startmonth']."-".$_POST['startday'];  

	}
	else
	{
echo "startdate is not valid, please try again";
	}

 /* Check startdate is valid  */
if (checkdate($_POST['endmonth'],$_POST['endday'],$_POST['endyear']) != NULL)
	{
$enddate = $_POST['endyear']."-".$_POST['endmonth']."-".$_POST['endday'];  

	}
	else
	{	
		echo "enddate is not valid, please try again";
	}


 /* validate variables  */  

if(empty($title)) echo("Enter a title");
if(empty($description)) echo("Enter a description!");


$query = "INSERT INTO tblevent VALUES(NULL, '$startdate', '$enddate', 
                     '$title', '$description', NULL)";

$result = mysql_query($query);

header('Location: http://localhost/index.php'); 

}
?>

[dalecosp]

Unfortunately, [man]header/man can't be used if any output has been given ... say, an error message like "startdate is not valid"....

There are several possible workarounds. One that I like is to initiate a session in PHP, and then assign the error message to a session variable instead of echoing it to the user. The page to which I'm redirecting contains the code to display the message. It could even do this by means of a javascript alert() method, to make it look more like some common applications.....

[mattastic]

Thanks for yor reply.

One that I like is to initiate a session in PHP, and then assign the error message to a session variable instead of echoing it to the user. The page to which I'm redirecting contains the code to display the message.

Sounds good, Could you explain this in a bit more details please? So I can use redirects after all?