Why can't I get and echo the cartId?

is there any mistake in the cookies part

[hughc]

--I got this code in a file called products.php

<a href="cart.php?action=add_item&id=<?php echo $row["cartId"];?>&qty=1">Add Item</a>

--and the function in the cart.php :

function AddItem($itemId, $qty)
{
// Will check whether or not this item
// already exists in the cart table.
// If it does, the UpdateItem function
// will be called instead

global $dbServer, $dbUser, $dbPass, $dbName;
echo "$itemId, $qty";
// Get a connection to the database
$cxn = @ConnectToDb($dbServer, $dbUser, $dbPass, $dbName);

// Check if this item already exists in the users cart table
$result = mysql_query("select count(*) from cart where cookieId = '" . GetCartId() . "' and PhoneID = $itemId");
$row = mysql_fetch_row($result);
$numRows = $row[0];

if($numRows == 0)
{
// This item doesn't exist in the users cart,
// we will add it with an insert query

@mysql_query("insert into cart(cookieId, PhoneID, qty) values('" . GetCartId() . "', $itemId, $qty)");
}
else
{
// This item already exists in the users cart,
// we will update it instead

UpdateItem($itemId, $qty);
}
}

and the function in db.php :

function GetCartId()
{
// This function will generate an encrypted string and
// will set it as a cookie using set_cookie. This will
// also be used as the cookieId field in the cart table

if(isset($_COOKIE["cartId"]))
{
return $_COOKIE["cartId"];
}
else
{
// There is no cookie set. We will set the cookie
// and return the value of the users session ID

session_start();
setcookie("cartId", session_id(), time() + ((3600 * 24) * 30));
return session_id();
}
}

I really wonder where is the problem that I can't get catId

[MrCrowley]

I tried this code :

function GetCartId() {
// This function will generate an encrypted string and
// will set it as a cookie using set_cookie. This will
// also be used as the cookieId field in the cart table

if(isset($_COOKIE["cartId"])) {
return $_COOKIE["cartId"];
} else {
// There is no cookie set. We will set the cookie
// and return the value of the users session ID

session_start();
setcookie("cartId", session_id(), time() + ((3600 * 24) * 30));
return session_id();
}
}

echo GetCartId();

in a php file, with nothing but it, and it works fine. What do you get when you try it?