[SOLVED] Warning: Cannot modify header information - headers already sent by (

DanielHardy · November 14, 2009

Hi All,

I am getting the following error message in a script that was previously working fine.

You can see it in action at

http://mi-linux.wlv.ac.uk/~0607197/login.php

I had the same problem on another page that was solved by removing white space before and after the php tags. This has not worked on this page.

Here is the code


<LINK rel="stylesheet" href="regal.css" type="text/css">
<script src="IEmarginFix.js" type="text/javascript"></script>
</head>

<BODY>

<div id="mainsite" ;text-align:center;">
<div id="toppic"><div id="topgap" style="height:70px;">




</div><div id="nav">

        	
                <div id="navgapper">

<div class="clean22" style="padding-top:7px;padding-left:5px; font-weight:bold;;height:30px;color:FFFFFF;">


<font color="#000000">
<?php
error_reporting (E_ALL);

if(isset($_COOKIE['ID_my_site'])){
echo " Hello  ";
echo $_COOKIE['ID_my_site'];



echo '<a href=logout.php><b> Logout</b></a>'."\n";}

else {
echo "Not Currently Signed In";
}
?>

</font>
</div>
            </div>
            
            
        	<div class="nav1">
        		<a href="regal1.php">Home</a>
        
        	</div>
            
       
         
        
        	<div class="nav1">
        		<a href="regal2.php">Events</a>
        	</div>
        
        
        
       		<div class="nav1">
       	 		<a href="regal3.php">Prices</a>
        	</div>
        
        	<div class="nav2">
        		<a href="book1.php">Book</a>
        	</div>
        
       	  <div class="nav1">
        		<a href="mailto:[email protected]">Contact Us</a>
       	  </div>
        	
</div>
</div><?php
// Connects to your Database
mysql_connect("localhost", "0607197", "12345") or die(mysql_error());
mysql_select_db("db0607197") or die(mysql_error());

//Checks if there is a login cookie
if(isset($_COOKIE['ID_my_site']))

//if there is, it logs you in and directes you to the members page
{
$username = $_COOKIE['ID_my_site'];
$pass = $_COOKIE['Key_my_site'];
$check = mysql_query("SELECT * FROM Users WHERE username = '$username'")or die(mysql_error());
while($info = mysql_fetch_array( $check ))
{
if ($pass != $info['password'])
{
}
else
{
header("Location: book1.php");

}
}
}

//if the login form is submitted
if (isset($_POST['submit'])) { // if form has been submitted

// makes sure they filled it in
if(!$_POST['username'] | !$_POST['pass'] | !$_POST['pass'] ) {
die('<h2><b>You did not fill in a required field.</b><a href="login.php"><font color="#b9c059">Back</a></font></h2>');
}
// checks it against the database

if (!get_magic_quotes_gpc()) {
$_POST['email'] = addslashes($_POST['email']);
}
$check = mysql_query("SELECT * FROM Users WHERE username = '".$_POST['username']."'")or die(mysql_error());

//Gives error if user dosen't exist
$check2 = mysql_num_rows($check);
if ($check2 == 0) {
die('<h2>No Such Account. <a href=register.php><font color="#b9c059">Click Here to Register</a></font></h2>');
}
while($info = mysql_fetch_array( $check ))
{
$_POST['pass'] = stripslashes($_POST['pass']);
$info['password'] = stripslashes($info['password']);
$_POST['pass'] = md5($_POST['pass']);

//gives error if the password is wrong
if ($_POST['pass'] != $info['password']) {
die('<h2> Incorrect password, please <a href=login.php><font color="#b9c059">Try again.</a></font>');
}

else
{

// if login is ok then we add a cookie
$_POST['username'] = stripslashes($_POST['username']);
$hour = time() + 3600;
setcookie(ID_my_site, $_POST['username'], $hour);
setcookie(Key_my_site, $_POST['pass'], $hour);

//then redirect them to the members area
header("Location: book1.php");
}
}
}

// if they are not logged in
?>

<div class="clean22" style="text-align:center;">
<div id="regform" style="padding-top:15px;">
<form action="<?php echo $_SERVER['PHP_SELF']?>" method="post">

<!-- Form To Capture Login Data -->

<center><table border="0" class="centeredtable" >
<tr ><td colspan="2"><h1>Login</h1></td></tr>
<tr ><td>Username:</td><td>
<input type="text" name="username" maxlength="40">
</td></tr>
<tr ><td>Password:</td><td>
<input type="password" name="pass" maxlength="50">
</td></tr>
<tr ><td colspan="2" >
<input type="submit" name="submit" value="Login">
</td >
</tr>
</table>
</form>

<p>
   Not Registered?
      


      <a href="register.php"><b><font color="#b9c059">Join</a></b></font>



<p><a href="adminlogin.php"><font color="#b9c059">Admins</font></a>
</div>




</div>
   </div>

I have included the HTML as well incase there are issues here.

Your help is, as always, greatly appreciated.

Thanks

Dan

rarebit · November 14, 2009

Certain actions require that no output is sent before them:

header("Location: book1.php");

and

setcookie(ID_my_site, $_POST['username'], $hour);
setcookie(Key_my_site, $_POST['pass'], $hour);

//then redirect them to the members area
header("Location: book1.php");

All of the above fall into this category.

You output data and then attempt to resend the header.

! Actually (still early) the cookies might not fall into this category... But 'header()' does for certain...

DanielHardy · November 14, 2009

Ideas on how to solve it without comprimising the functionality?

Never come accross this before. Weird how it worked before though is it not?

Thanks

rarebit · November 14, 2009

There's various ways, all depending upon how you code...

Some people use a set set of buffering functions, see around here:

http://uk2.php.net/manual/en/function.ob-start.php

Me I code so that header critical stuff is processed prior to any output, even if it means an extra variable.

mga_ka_php · November 14, 2009

put your code with header("Location: book1.php"); at the top. you already had declared header.

or replace header("Location: book1.php"); with echo '<META http-equiv="refresh" content="1;URL=page.php">';

DanielHardy · November 14, 2009

Using the Meta tags didn't work, interesting how you can use these in such a way though

What piece of code are you suggesting I move exactly?

rarebit · November 14, 2009

All 'echo' and 'print', also anything outside the php code tags are sent directly to the output stream...

rarebit · November 14, 2009

p.s. The meta tag version works at the browser level and can be overidden, whereas 'header' works at the server level.

mga_ka_php · November 14, 2009

are you sure the meta didn't work, i use it a lot without a problem.

if the meta didn't work. move

<?php
// Connects to your Database
mysql_connect("localhost", "0607197", "12345") or die(mysql_error());
mysql_select_db("db0607197") or die(mysql_error());

//Checks if there is a login cookie
if(isset($_COOKIE['ID_my_site']))
//if there is, it logs you in and directes you to the members page
{
$username = $_COOKIE['ID_my_site'];
$pass = $_COOKIE['Key_my_site'];
$check = mysql_query("SELECT * FROM Users WHERE username = '$username'")or die(mysql_error());
while($info = mysql_fetch_array( $check )){
	if ($pass != $info['password']){
	}else{
		header("Location: book1.php");

	}
}
}

//if the login form is submitted
if (isset($_POST['submit'])) { // if form has been submitted

// makes sure they filled it in
if(!$_POST['username'] | !$_POST['pass'] | !$_POST['pass'] ) {
die('<h2><b>You did not fill in a required field.</b><a href="login.php"><font color="#b9c059">Back</a></font></h2>');
}
// checks it against the database

if (!get_magic_quotes_gpc()) {
$_POST['email'] = addslashes($_POST['email']);
}
$check = mysql_query("SELECT * FROM Users WHERE username = '".$_POST['username']."'")or die(mysql_error());

//Gives error if user dosen't exist
$check2 = mysql_num_rows($check);
if ($check2 == 0) {
die('<h2>No Such Account. <a href=register.php><font color="#b9c059">Click Here to Register</a></font></h2>');
}
while($info = mysql_fetch_array( $check ))
{
$_POST['pass'] = stripslashes($_POST['pass']);
$info['password'] = stripslashes($info['password']);
$_POST['pass'] = md5($_POST['pass']);

//gives error if the password is wrong
if ($_POST['pass'] != $info['password']) {
die('<h2> Incorrect password, please <a href=login.php><font color="#b9c059">Try again.</a></font>');
}

else
{

// if login is ok then we add a cookie
$_POST['username'] = stripslashes($_POST['username']);
$hour = time() + 3600;
setcookie(ID_my_site, $_POST['username'], $hour);
setcookie(Key_my_site, $_POST['pass'], $hour);

//then redirect them to the members area
header("Location: book1.php");
}
}
}

// if they are not logged in
?>

before <html>

if your going to use header(), always put that before <html>

DanielHardy · November 14, 2009

I used regiemon's method. Will remember to do this in future.

The php code that included headers in my other page was indeed before the html. I also noticed that I was trying to redirect the page to itself in certain instances. So this was causing problems too.

Thanks for all of your help.

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[SOLVED] Warning: Cannot modify header information - headers already sent by (

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