Im getting a blank page in php [closed]

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. Closed 11 years ago. 开发者_运维技巧

I'm trying to create a PHP e-mail activation system for my users, and when I run my script, it returns a blank page and my database was not updated. Any help is appreciated.

Here is my code:

<?php

session_start()

$host="localhost"; 
$username="root"; 
$password="power1"; 
$db_name="members"; 
$tbl_name="users";

$link  = mysql_connect($host, $username, $password)or die("cannot connect. Please contact us");
mysql_select_db($db_name)or die("cannot select DB. Please contact us");

$queryString = $_SERVER['QUERY_STRING'];

if(isset($_SESSION[$queryString])) {
  $query = "SELECT * 
              FROM users 
             WHERE email = '$_SESSION[$queryString]'";
  $result = mysql_query($query) or die(mysql_error());
  while($row = mysql_fetch_array($result)) {
    if ($queryString == $row[activationkey]) {
      echo "Congratulations! You have succesfully activated you account. You may now login.";

      $sql = ("UPDATE users 
                 SET activationkey = '' 
                 AND status = 'activated' 
               WHERE username = ".$row['username']);

      if (!mysql_query($sql)) {
        die('Error: ' . mysql_error());
      }
    }
  }
} ?>

---

In your code, activationkey is an uninitialized constant. You probably meant it to be a string.

Change this line:

if ($queryString == $row[activationkey]){

to this:

if ($queryString == $row['activationkey']){

And since you are accessing the elements of $row via string indexes, rather than numeric ones, you'll also want to change:

while($row = mysql_fetch_array($result)){

to:

while($row = mysql_fetch_assoc($result)){

Also, since you are accessing a session, you probably want to call session_start() before the first reference to $_SESSION.

And finally, your code may be sending a malformed query to the database. Try changing this line:

$query = "SELECT * FROM users WHERE email='$_SESSION[$queryString]'";

to this:

$query = "SELECT * FROM users WHERE email='" . mysql_real_escape_string($_SESSION[$queryString]) . "'";

---

You probably just have an error... PHP is notorious for blowing up and not letting you know about it. Try adding this to the top of your code and running the file:

error_reporting(E_ALL);
ini_set('display_errors', '1');

Just don't leave it in when you make you're application available to other users..

---

Your query may not be returning any value, try to print the sql and see what's wrong with the query

---

while using sessions, you need to give

  <?php
   session_start();

at the beginning of the script.

---

I think the lines with $_SESSION[$queryString] may be your issue, try replacing all instances with $_SESSION['QUERY_STRING'] or $queryString

---

only message is printed if you execution goes in

if ($queryString == $row[activationkey])

statement..

I think $queryString does not get any match with all db vals...

one more thing if activationkey is table column then it has to be covered by single or double quotes like this $row['activationkey']