Passing Variables in the url

ronanmckibbin

I'm trying to pass a variable from one piece of code to another so that a shopper can click on an item and using a Select statement the item_id is found in the database and passed to the other form.

I 'm able to do this but the url :
http://172.179.88.110/store/showitem.php?3
does not tell the piece of code that the variable is passed to its name.

I have tried the url :
http://172.179.88.110/store/showitem.php?item_id=3
and things work well
I have added a copy of the code that generates the variable

Ronan

<?php

$conn = mysql_connect("localhost", "u0118292") or die(mysql_error());
// Pick the db to use
mysql_select_db("mydb",$conn) or die(mysql_error());

$display_block = "<H1>My Categories</H1><P>Select a category to see its items.</P>";

//show categories first
$get_cats = "select id, cat_title,cat_desc from store_categories order by cat_title";
$get_cats_res = mysql_query($get_cats) or die(mysql_error());

if (mysql_num_rows($get_cats_res) < 1)
{
$display_block = "<P><EM>SORRY, no cats here</EM></P>";
}
else
{
while ($cats = mysql_fetch_array($get_cats_res))
{
$cat_id = $cats[id];
$cat_title = strtoupper(stripslashes($cats[cat_title]));
$cat_desc = stripslashes($cats[cat_desc]);

	$display_block .= "<P><strong><a href=\"$_SERVER[PHP_SELF]?cat_id=$cat_id\">$cat_title</a></strong><BR>$cat_desc</P>";



	if ($_GET[cat_id] == $cat_id)
	{

		//get items
		$get_items = "select id, item_title, item_price from store_items where cat_id = $cat_id order by item_title";
		$get_items_res = mysql_query($get_items) or die(mysql_error());

		if (mysql_num_rows($get_items_res) < 1)
		{
			$display_block = "<P><EM>SORRY, no items in this cat</EM></P>";
		}
		else
		{
			$display_block .= "<ul>";

			while ($items = mysql_fetch_array($get_items_res))
			{
				$item_id = $items[id];
				$item_title = stripslashes($items[item_title]);
				$item_price = $items[item_price];

				$display_block .= "<li><a href=\"showitem.php?$item_id\">$item_title</a></strong> (£$item_price)";
			}
			$display_block .= "</ul>";
		}
	}
}

}
?>
<HTML>
<HEAD>
<TITLE>My Categories</TITLE>
</HEAD>
<BODY>
<? print $display_block; ?>
</BODY>
</HTML>

jayant

Change:
<a href=\"showitem.php?$item_id\">$item_title</a>
to
<a href=\"showitem.php?item_id=$item_id\">$item_title</a>

So all links will be like showitem.php?item_id=12345 instead if showitem.php?12345

If you really want showitem.php?12345 , take a look at $_SERVER['QUERY_STRING']

adamgeorge

Ah huh. That's how data is passed in the query string.

You simply append a "?" to the end of the url, and then list your variables like so:

var1=2&var2=4&var3=7

where the format is variable=value, and use the "&" character to seperate variables.

note that when you didn't specify a variable name, and only a value, the variable wasn't passed. You must provide a name for all variables you pass in the query string.

Notice in this piece of code from your sample code, you didn't provide a name for the variable you were passing, only a value:

$display_block .= "<li><a href=\"showitem.php?$item_id\">

you should give it a name like so:

$display_block .= "<li><a href=\"showitem.php?items_id=$item_id\">

Then when you want to access this variable on the showitem.php script you simply access it like so:

$item_id = $_GET["item_id"];

I hope that was what you were after, I wasn't quite sure, cause your question was a bit obscure.

cya man,
- Adam 🙂

adamgeorge

Ha. Three minutes too late I was. I did something like that the other day, except when I read the other guys response I realised I was way off lol.

At least this time my advice doesn't contradict lol.

cya
-Adam 🙂

ronanmckibbin

Thanks for the help. It works well.
Until the next problem
Ronan