Okay, I had a few minutes, so I added all the mystatements and provided some initializers to get around the error messages.

Your code still doesn't do anything:

#!/usr/bin/perl
use strict;
use warnings;

my $str = "1,2,3,4,5";
my @array = ();

my ($ids, $attri) = split /,/, $str;
print "    \$ids:  [$ids]\n";
print "  \$attri:  [$attri]\n";

splice (@array,$ids, 1);
print "  \@array:\n";
my $array_index = 0;
foreach my $array_element (@array) {
    print "            [$array_index]:  [$array_element]\n";
}

print "Okay, now what?\n";

sub refreshdisplay{
    my $id=0;
    my $arraylist = "";
    for($id=0;$id<=$#array;$id++){
        if($id == 0){
            $arraylist = "$array[0]";
        }
        else{
            $arraylist .= "$id,$array[$id]\n";    
        }
    }
}
[download]

Yields:

S:\Steve\Dev\PerlMonks\P-2017-08-15@0704-combobox>perl combobox0b.pl
    $ids:  [1]
  $attri:  [2]
splice() offset past end of array at combobox0b.pl line 12.
  @array:
Okay, now what?

S:\Steve\Dev\PerlMonks\P-2017-08-15@0704-combobox>
[download]