problem with arrays in URL query

[wkilc]

I tired something earlier, with no luck...  so I'm taking a few steps back.  I've been working this one complicated page for days...

 

Here's what used to work:

 

//the current URL
$page_name = $_SERVER["REQUEST_URI"];

//remove any old limit from query before requesting a new limit
$tmp = array();
foreach ($_GET as $fld => $val)
    if ($fld != 'limit')
         $tmp[] = $fld . '=' . $val;
$page_name = $_SERVER['SCRIPT_NAME'] . '?' . implode('&',$tmp);

//sets the number of records to be displayed on the page
<form>
<select name="link">
<option value="<? echo "$page_name" ?>&limit=25">25 records per page</option>
<option value="<? echo "$page_name" ?>&limit=50">50 records per page</option>
<option value="<? echo "$page_name" ?>&limit=100">100 records per page</option>
</select>
</form>

 

This grabs the current URL, and clears the &limit= string before a new limit is introduced to avoid:

www.example.com/test.php?sub=math[]&sub[]=science&limit=25&limit=50&limit=100

 

The problem, is that my URL is already querying an array:

www.example.com/test.php?sub[]=math&sub[]=science

 

So now, when I apply the form above to this URL set the new limit to 50 records per page the URL actually becomes:

www.example.com/test.php?sub=Array&limit=50

Warning: Invalid argument supplied for foreach() ... on line 147

 

I guess I've broken the array?

 

//line 147 
echo "subject:<BR />";
if(!empty($_GET['sub']))
  foreach($_GET['sub'] as $sub) {
    echo "$sub <BR />\n";
  }

 

~Wayne

 

[sasa]

 $page_name = $_SERVER["REQUEST_URI"];
$page_name = preg_replace('/&?limit=\d+/','',$page_name);

[wkilc]

THANK YOU!!!!

 

I was trying to simplify for the purpose of posting... the problem now is...

 

I've got more than one value:

 

there's also &start= which tells it if we're on the first, second, third, etc.. of the displayed pages.

 

The idea is that I want to clear the one I'm changing while keeping the other.

www.example.com/test.php?sub=math[]&sub[]=science&limit=50&start=50

 

Can't do both like this, right?

 

$page_name = $_SERVER["REQUEST_URI"];
$page_name = preg_replace('/&?limit=\d+/','',$page_name); 
$page_name = preg_replace('/&?start=\d+/','',$page_name);

 

~Wayne

[sasa]

yes if start is number

[wkilc]

$page_name = $_SERVER["REQUEST_URI"];
$page_name = preg_replace('/&?limit=\d+/','',$page_name);
$page_name = preg_replace('/&?start=\d+/','',$page_name);

 

This doesn't work for the &start= link comes out as "sub=Array" again.

 

If I change it to this:

$page_name = $_SERVER["REQUEST_URI"];
$page_name = preg_replace('/&?limit=\d+/','',$page_name);
$page_name2 = preg_replace('/&?start=\d+/','',$page_name);

 

Then it obviously doesn't  flush &limit= anymore.

 

I'm sorry...

 

~Wayne