Warning: Cannot add header information - Please help me ditch this error.

Keaner

I'm trying to encapsulate my whole page in tables. Since starting this, one of my pages (Login screen) spits out this error:

Warning: Cannot add header information - headers already sent by (output started at /home/html/index.php:8) in /home/html/index.php on line 30

Now does anybody know how to fix this? Here is line 30:

if ($username == "admin") {
   if ($password == $checkPass) {
30-> header("Location: main.php");
   }
}

Any help is greatly appreciated.

laserlight

very likely you output something before the header(), and/or you have a blank line at the top of the script.

Keaner

Ok, I'm not sure if it's either. Here's my script:

<HTML>
<HEAD>
<TITLE>Public Information and Library Resources Board</TITLE>
</HEAD>

<BODY>

<?
include("details.inc");

if(isset($_POST['username']) && isset($_POST['password']))
{
$username=$_POST['username'];
$password=$_POST['password'];

$query="SELECT * FROM login WHERE username='$username'";
$result=mysql_query($query);
$num=mysql_numrows($result);

mysql_close();
}
$i=0;
while ($i < $num) {

   $checkName=mysql_result($result,$i,"username");
   $checkPass=mysql_result($result,$i,"password");

if ($username == "admin") {
   if ($password == $checkPass) {
       header("Location: main.php");
   }
}

if ($username != "admin") {
   if ($username == $checkName) {
      if ($password == $checkPass) {
         header("Location: searchForm2.php");
      }
   }
}
$i++;
}

?>
<TABLE BORDER=0 WIDTH=800 ALIGN="CENTER">
<TR ALIGN="CENTER">
   <TD><CENTER><IMG SRC="inventorylogo.jpg"></CENTER><P>
   </TD>
</TR>
<TR ALIGN="CENTER">
   <TD><P>
      <CENTER><H2>Login</H2></CENTER><P>
      <HR><P>
   </TD>
</TR>

<TR ALIGN="CENTER">
   <TD>
      <form name="login" method=post action="<?php echo $PHP_SELF?>">
     <TABLE BORDER=1 WIDTH=30% ALIGN="CENTER">
      <TR ALIGN="CENTER">
         <TD>Username
         </TD>
         <TD><Input type="text" name="username" size="25">
         </TD>
      </TR>
      <TR ALIGN="CENTER">
         <TD>Password
         </TD>
         <TD><Input type="password" name="password" size="25">
         </TD>
     </TR>
</TABLE>
</TD></TR>
<TR ALIGN="CENTER">
   <TD>
      <CENTER><input type="submit" name="submit" value="Login">
       <Input type="reset" name="reset" value="Restart"></CENTER>
   </TD>
</TR>
</FORM>

<?
include("footer.inc");
?>

laserlight

"<HTML>
<HEAD>
<TITLE>Public Information and Library Resources Board</TITLE>
</HEAD>

<BODY>"

That is an example of output before the header()

you should shift this to below the potential header()

Keaner

That did it. Thanks

k89mmmk

And you solved a problem for me before I even asked! Thanks.

trooper

Another more robust solution is to use ob_start and ob_end_flush functions (or a variation of)

found here and here

This will then allow you to put header information wherever you want to.

HTH