new_2_perl wrote:

When the user submits the form my $input will only give me the last value from the list box they selected.

I see this all the time and it's invariably from someone who is using a broken "hand-rolled" alternative to CGI.pm. CGI.pm, if you ask for the form's value in scalar context, will return the first value for the form element in question. Alternatives to CGI.pm, however, often have code like the following:

foreach $pair (@pairs){
    ($name, $value) = split(/=/, $pair);
    $value =~ tr/+/ /;
    $value =~ s/%0D%0A/\n/g;
    $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
    $FORM{$name} = $value;
}
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There are a variety of problems with this, but the line that usually causes problems like what you are experiencing is the $FORM{$name} = $value; line. This one will simply overwrite the last value of $FORM{$name} rather than adding a new value.

See "use CGI or die;" for more complete information as to why using alternatives to CGI.pm are usually a poor idea.

Cheers,
Ovid

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Thanks guys. I'm using CGI.pm now and making it just return me an array of the values is very easy. Thanks again

 FETCHING THE VALUE OR VALUES OF A SINGLE NAMED PARAMETER:
 
           @values = $query->param('foo');
 
                     -or-
 
           $value = $query->param('foo');
 
Pass the param() method a single argument to fetch the value of the na
+med
parameter. If the parameter is multivalued (e.g. from multiple selecti
+ons in
a scrolling list), you can ask to receive an array. Otherwise the meth
+od will return a single value.
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Update, since this was the first in a search for "perl cgi param multiple values."

Newer versions of CGI.pm will generate a warning if you use

my @vals = $q->param('input');
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Better to use

my @vals = $q->multi_param('input');
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From man CGI: "Warning - calling param() in list context can lead to vulnerabilities if you do not sanitise user input as it is possible to inject other param keys and values into your code. This is why the multi_param() method exists, to make it clear that a list is being returned, note that param() can still be called in list context and will return a list for back compatibility."

And "If you call param() in list context with an argument a warning will be raised by CGI.pm, you can disable this warning by setting $CGI::LIST_CONTEXT_WARN to 0 or by using the multi_param() method instead"

input[];

For the full example:
    <form>
       <select NAME="input[]" SIZE=3 MULTIPLE>
          <option VALUE="opt1">option1
          <option VALUE="opt2">option2
          <option SELECTED VALUE="opt3">option3
       </select>
    </form>
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a.
<select name="myname" multiple>

b.
<select name="myname[]" multiple>
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You would name it whatever you want. You would then access multiple valuse by assigning to an array when requesting the values:

my @selected = $query->param("my_multiple_select");
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Or just use it in a list context:

foreach my $sel ( @{$query->param("select")} ){
    ...
}
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You might also want to name it myname[] just to remind yourself that multiple values are allowed.

Have a look at CGI::State. If you follow a naming convention it sets out it will take a CGI.pm query object and turn it into a multidimensional data structure.

The name is off and it wouldn't be the best thing for maintainability but I can see how it could be handy.

Clayton aka "tex"