Passing array to function

I am trying to write a function that builds a multiple-choice drop down list. As such, I need to specify an array in the name attribute of the <select> tag. I am trying to pass a parameter to the function which gets used as this name attribute, but seem to be having problems with the square brackets. In the example below, I would like to submit the $elementname variable to a function, but can't get it to take the '[' and ']' characters. My resultant $_POST[] variable is empty. Any hints? HARD-CODED VERSION echo "<select name='cgroup_1[]' multiple size='5'>"; echo "<option value = '$chon_group_a[1]' selected>$chon_group_a[1]</option>"; echo "<option value = '$chon_group_a[2]'>$chon_group_a[2]</option>"; echo "<option value = '$chon_group_a[3]'>$chon_group_a[3]</option>"; echo "<option value = '$chon_group_a[4]'>$chon_group_a[4]</option>"; echo "</select>"; //the $chon_group_a is a locally defined array that does not seem to be causing any problems DESIRED FUNCTION VERSION $elementname="cgroup_1[]"; $elementsarray=$chon_group_a; PrintOptionBox($elementname,$elementsarray);