thanks for your reply ,but the unquoted select1 select2 will generate syntax error . The Source code of the form webpage I want to query is written in php as follows 
...
<form name="geneCompareTwo" method="post" action="geneCompareTwo2.php"
+>
...
<select name="ontologies[]" multiple="yes"    size="4">
<option selected value="All">All</option>
<option value="biological_process">Biological Process</option>
<option value="cellular_component">Cellular Component</option>
<option value="molecular_function">Molecular Function</option>
</select>

[download]
if I want to simulate http query using lwp method as follows 
my $response=$browser->post($url,["ontologies[]" => "ALL"])

[download]
it still doesn't work

In reply to Re^2: how to post multiple select list through LWP::agent by NPhard
in thread how to post multiple select list through LWP::agent by NPhard

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