That can be done using JavaScript.

To select multiple items from a drop-down list in the same form, you have to store the selected items in another list in the form (and provide a facility to delete item from that list). Upon submit, the items in that list need to be selected, otherwise they won't make it into the CGI params. Get a book covering JavaScript, or visit one of the zillion sites covering JavaScript, listboxes and shopping carts.

Anyways, here's how you can do that. 

#!/usr/bin/perl
use CGI qw(:all);

my $js = <<EOH;
function addFromList() {
    var popup = document.getElementById('title');
    var olist = document.getElementById('ordered_items');
    for (var i = 0; i<popup.options.length;i++) {
        if(popup.options[i].selected) {
            var item = popup.options[i].value;
            // if you want to allow multiple instances
            // of the same item in your list, remove the
            // next three lines.
            for(var j = 0; j<olist.options.length; j++) {
                if (olist.options[j].value == item) return;
            } 
            var opt  = new Option(item,item,false,false);
            olist.options[olist.options.length] = opt;
        } 
    } 
} 
function addFromEntry () {
    var olist = document.getElementById('ordered_items');
    var entry = document.getElementById('requesttext');
    if(entry.value != '') {
        var opt = new Option(entry.value,entry.value, false,false);
        olist.options[olist.options.length] = opt;
    }
} 
function removeFromList () {
    var olist = document.getElementById('ordered_items');
    for (var i = olist.options.length - 1; i>=0; i--) {
        if (olist.options[i].selected) {
            olist.options[i] = null;
        } 
    } 
    olist.selectedIndex = -1;
} 
function selectAll() {
    var olist = document.getElementById('ordered_items');
    for (var i = 0; i<olist.options.length; i++) {
        olist.options[i].selected = true;
    } 
} 
EOH
print header(), start_html (-script => $js) ;

#=====================================================================
+==========
my @titlelist;
open FILE, "<$ENV{'DOCUMENT_ROOT'}/data/vault/titlelist.txt" or die $!
+;
     chomp (@titlelist = <FILE>);
close FILE;

print br() x 5;
print start_form( action=>'/cgi-bin/admin.pl' );
    print table( {class=>'user_form'},
        Tr( td( {width=>'55%'},  'Select items' ),
            td( {width=>'35%'},  popup_menu( -id=> 'title', -name=>'ti
+tle', -values=>\@titlelist )),
            td( {width=>'10%'},  button(-name => 'add', -value => "add
+", -onclick => 'addFromList()'))),
            
        Tr( td( 'ask for something else if it is not listed on drop do
+wn menu'  ),
            td( textfield( -name=>'requesttext',-id => 'requesttext' )
+),
            td( button(-name => 'request', -value => 'request', -oncli
+ck => 'addFromEntry()'))),

        Tr( td( 'Your Order list'),
            td( popup_menu(-name => 'ordered_items', -multiple => 1, -
+id => 'ordered_items')),
            td( button(-name => 'delete', -value => 'remove',-onclick 
+=> 'removeFromList()'))),

        Tr( td( 'Soemthing to remark on order' ),
            td( {colspan=>2},  textarea( -name=>'remark', -rows=>6, -c
+olumns=>35 ))),
     
        Tr( td(  a( {href=>'/cgi-bin/show.pl?name=showbook'}, font( {s
+ize=>3, color=>'yellow'}, 'Change Order' ))),
            td( {colspan=>2},  submit( -name => 'Order!', -onclick => 
+'selectAll()' )))
    );

      print hidden(-name=>'date',  -value=>$date);
      print hidden(-name=>'host',  -value=>$host);
print end_form();
print br() x 5;
#=====================================================================
+==========

if(param('ordered_items')) {
    print h3('Your Order'),ul(map{li($_)} param('ordered_items'));
} 
if(param('remark')) {
    print h3('Your remark'),param('remark');
} 
print end_html;
__END__

[download]

I would rather use the POST method with that form.

If you don't want to use JavaScript, you will have to use a list box with multiple select turned on (not a drop down); the third possibility is to have your users submit the form after each select, and store the selected items somewhere on the server side, e.g. in a CGI::Session object.

update: I see you've implemented this at your server... as easy as cut-n-paste, no? But come on. Read the code before you include it, and include only as much as makes sense:

You included the whole bunch from the line my $js = <<EOH; so you have the line 

print header(), start_html (-script => $js) ;

[download]
in it. Which means

Also, you could set the ordered-items list box to some initial width (via css), the small thingy in there just looks funny :-)

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re: How to select many times from a drop down menu in the same form by shmem
in thread How to select many times from a drop down menu in the same form by Nik

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