Greetings, folks.
Here's today's little problem I'm having...
When entering one iteration of my script (one web page), if certain parameters are not set, I'm trying to give the user a message, and a button that will send them back to the last page with all the appropriate fields being passed. The param('action') is what I'm using to determine which function (ie: page) you are supposed to go to. When I get to the page, I'm dumping parameters to see how it's working, since I've been having problems deleting 'action'. delete('action') gave me a hassle, and param('action',undef) methinks was just appending an undef to the array param('action') rather then setting it. I'm using a hidden field to re-set 'action' in the new form.
The function code looks like this: 
sub load_items {
    ($source, $po) = ( param('source'),param('po') );
    if(!$source || !$po){
        param(-name=>'action', -value=>'');
        print header(),
            start_html(-title=>"Title",
                   -style=>{-code=>$got_no_style},
                     -BGCOLOR=>'tan');
        print h1({class=>'Default'},'ERROR'),
            p({class=>'Error'},$mess_nosource);
        print start_multipart_form(),
            submit(-name=>'junk', -label=>'Return to Source/Ship Metho
+d/PO'),
            hidden(-name=>'flags', -value=>$flags),
            hidden(-name=>'source', -value=>uc($source)),
            hidden(-name=>'po', -value=>$po),
            hidden(-name=>'file', -value=>param($file)),
            hidden(-name=>'action', -value=>'Accept These Customers');
            end_form(),"</CENTER>";
        debug_plop();
    } else {
#not hit right now
    }
}

[download]
$mess_nosource is just the text on the screen. debug_plop just dumps my params. The output looks fine, but the dump looks like: 
key source value zot
key sm value 85
key po value 
key file value C:\temp\CGItemp4840001
key flags value 2345
key action value

[download]
My problem is, the line param(-name=>'action',-value=>'') successfully deletes that parameter, but my hidden() field with a name of 'action' is now not passing along the value.
Please enlighten me.
-rev

In reply to CGI: Trouble changing/deleting a param by Reverend Phil

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