PHP Login System ~ session.register and session.start errors

问题

I'm newish to php and i'm trying to use a login system here:

<table width="300" border="0" align="center" cellpadding="0" cellspacing="1"     bgcolor="#CCCCCC">
<tr>
<form action="/?module=admin&n=checklogin" method="post" enctype="multipart/form-data"     name="form1" id="form1">
<td>
<table width="100%" border="0" cellpadding="3" cellspacing="1" bgcolor="#FFFFFF">
<tr>
<td colspan="3"><strong>Administrator Login </strong></td>
</tr>
<tr>
<td width="78">Username</td>
<td width="6">:</td>
<td width="294"><input type="text" name="myusername" id="myusername"></td>
</tr>
<tr>
<td>Password</td>
<td>:</td>
<td><input name="mypassword" type="password" id="mypassword"></td>
</tr>
<tr>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td> <button type="submit" name="Submit">Login</button>
<img src="../images/ajax-loader.gif" width="16" height="16" style="display: none"/>
<script>
$("button").click(function () {
$("img").show("slow");
});
</script>
</td>
</tr>
</table>
</td>
</form>
</tr>
</table>

This is the code for checklogin.php

<?php
error_reporting(E_ALL);
$host="localhost"; // Host name 
$username="david_bpd"; // Mysql username 
$password="documents123456"; // Mysql password 
$db_name="david_bpd"; // Database name 
$tbl_name="members"; // Table name

// Connect to server and select databse.
mysql_connect("$host", "$username", "$password")or die(mysql_error()); 
mysql_select_db("$db_name")or die("cannot select DB");

// username and password sent from form 
$myusername=$_POST['myusername']; 
$mypassword=$_POST['mypassword'];

// To protect MySQL injection (more detail about MySQL injection)    
$myusername = stripslashes($myusername);
$mypassword = stripslashes($mypassword);
$myusername = mysql_real_escape_string($myusername);
$mypassword = mysql_real_escape_string($mypassword);

$sql="SELECT * FROM $tbl_name WHERE username='$myusername' and password='$mypassword'";
$result=mysql_query($sql) or die(mysql_error());

// Mysql_num_row is counting table row
$count=mysql_num_rows($result);
// If result matched $myusername and $mypassword, table row must be 1 row


if($count==1){
// Register $myusername, $mypassword and redirect to file "login_success.php"
session_register("myusername");
session_register("mypassword"); 
echo "<meta http-equiv='refresh' content='0;url=/?module=admin&n=Login_success'/>";
}
elseif($count==0) {
echo "<meta http-equiv='refresh' content='0;url=/?module=admin&n=Login_Unsuccessful'/>";
}

?>

But whenever I try to loin with the correct credentials i get these errors:

Deprecated: Function session_register() is deprecated in /home/david/public_html/bowlplexdoubles/admin/checklogin.php on line 45

Warning: session_register() [function.session-register]: Cannot send session cache limiter - headers already sent (output started at /home/david/public_html/bowlplexdoubles/index.php:12) in /home/david/public_html/bowlplexdoubles/admin/checklogin.php on line 45

Deprecated: Function session_register() is deprecated in /home/david/public_html/bowlplexdoubles/admin/checklogin.php on line 46

and

Warning: Unknown: Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively in Unknown on line 0

I don't know what to do next

Any help would be appreciated,

Thanks

回答1:

Something being "deprecated" means that there is a new/better way to do things. In this case, instead of doing session_register you can just create a variable using

$_SESSION['someKey'] = someValue;

Then upon loading the admin page you can do the following

if (isset($_SESSION['someKey']) {
    if ($_SESSION['somekey'] == someValue) {
        //User should be allowed to be on page
    }
    else
        Header("Location: someotherpage.php");
}
else
    Header("Location: someotherpage.php");

回答2:

You should use

<?php session_start(); at the top of both pages (and all using sessions), and set your session variables like this:

$_SESSION['myusername'] = $myusername;

$_SESSION['mypassword'] = $mypassword;

来源：https://stackoverflow.com/questions/6398603/php-login-system-session-register-and-session-start-errors

标签

php

session