Checking variables exist

Matt_Parsons

I have a script that queries a database, which works fine.
Now i want to allow a user to be able to change the way its ordered by using a dropdown menu, i managed to do this ok.

I also want the user to be able to filter the data, this i can also do! Combining the two functions together is proving a nightmare.

When a user selects order by date from the jump menu, the page is reloaded and depending on option selected the variable is added to the url, e.g. view.php?orderby=date

When the user selects the filter option it will do the same as above e.g. view.php?category=21

I have coded it so that both jump menus look at the url and add there variable on the end using
$PHP_SELF . "?" .$HTTP_SERVER_VARS['QUERY_STRING'];

The trouble comes when the variables have already been set so $PHP_SELF . "?" .$HTTP_SERVER_VARS['QUERY_STRING']; causes probs
e.g. view.php?category=21 could become view.php?category=21?category=21
How can i tell ifs it already set and if so change the existing variable to contain the new value.

John_Canyon

Post your <form> here so we can take a look at it and have a better idea of what you are trying to accomplish.

If it were me, I would put both options in the same form, that way the variables are passed everytime the form is changed or in this case an option is changed.

If its in between screens that they select these options then hide it in a hidden field.

John

merkinmuffley

i agree, you should have one form that has the 2 menus; if the form has a GET method, then the values will be appended to the url.

<?
$query = "SELECT * FROM MyTable";
if ($_GET['category'])
    $query .= " WHERE Category=".$_GET['category'];
if ($_GET['orderby'])
    $query .= " ORDER BY ".$_GET['orderby'];
?>
<form method="get" action="<?=$PHP_SELF?>">

<select name="orderby" onchange="this.form.submit()">
<option value="">Default
<option value="date">Date
</select>

<select name="category" onchange="this.form.submit()">
<option value="">All
<option value="21">21
</select>

</form>

Matt_Parsons

This is the sample code of my form

<form name="form1">
<select name="orderby" onChange="MM_jumpMenu('parent',this,0)">
<option value="view.php?orderby=title" >Title</option>
<option value="view.php?orderby=date" >Date</option>
<option value="view.php?orderby=location" >Location</option>
</select>
</form>

Pretty basic really. I did not think to put both jump menu's in the same form.
I will see how i get on, but thanks for the advice.

merkinmuffley

in case you want more advice, here's mine: don't let MacroMedia software write your code for you :]