Question

Im currently new to PHP and JQuery after having using ASP.Net and C Sharp for the 2 years. I have this major problem in which i require some assistance in.

I have a HTML <input type="submit" id="btnWL" value="Add to Wishlist"> button. Basically when this button is pressed a table called ‘wishlist’ in the database is checked to see if the current product is already in a wishlist. If no the button will trigger a database save else it will return a JQuery alert pop up error message.

I having difficulty in passing 2 PHP variables: $_SESSION["username"] and $_GET["ProductId"] into this JQuery method:

<script type="text/javascript">
            $(document).ready(function() {
                $('#btnWL').live('click', function() {
                    $.post("addToWishlist.php"); 
                });
            });
</script>

As you can see this JQuery method must pass those values to an external PHP File which checks for an already exsisting record in the ‘wishist’ table with those details.

<?php    

    $WishlistDAL = new WishlistDAL();
    $result = $WishlistDAL->get_ProductInWishlistById($_GET["ProductId"]);

    if (isset($_POST["isPostBack"])) {
     if (isset($_SESSION["username"])) {
        if (isset($_GET["btnWL"])) {            
            //Check if ProductId is in Cart            
            if (mssql_num_rows($result)>0)
            {
                //Return an error
                //Sumhow this has to trigger an alert box in the above JQuery method

            }
            else
            {
                //Write in Wishlist Table
                $WishlistDAL->insert_ProductInWishlist($_GET["ProductId"], $_SESSION["username"]);                
            }        
        }    
      }
      else
      {
          //Return Error
      }      
    }
?>

Another problem I have is then displaying an alert box using the same JQuery method for any errors that where generated in the php file.

Any Ideas how I can implement this logic? Thanks in advance.

Answer 1

Your “$.post()” call isn’t passing any parameters, and has no callback for interpreting the results:

$.post('addToWishlist.php', { username: something, password: something }, function (response) {
});

The “something” and “something” would probably come from your input fields, so:

$.post('addToWishlist.php', { username: $('#username').val(), password: $('#password').val() }, function (response) {
});

Now the callback function would interpret the response from the server:

$.post('addToWishlist.php', { username: $('#username').val(), password: $('#password').val() }, function (response) {
  if (response === "FAIL") {
    alert("fail");
  }
  else {
    // ... whatever ...
  }
});

Exactly what that does depends on your server code; that “FAIL” response is something I just made up as an example of course.