Assuming that the code you've given so far is correct, then this should do the iteration for you: 
$webpage = $browser->post($form_url, [
   username => $username,
   (map {widget => $widget{$_}} (keys %widget)),
   created => '1126175051'
],Content_Type => 'form-data'));

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Although I find it a bit odd that widget is a hash. If perhaps widget is really an array, then the code you need is this: 
$webpage = $browser->post($form_url, [
   username => $username,
   (map {widget => $_} @widget),
   created => '1126175051'
],Content_Type => 'form-data'));

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To debug this, I would strongly recommend doing something like this in your code: 
my $lwparg = [
   username => $username,
   (map {widget => $widget{$_}} (keys %widget)),
   created => '1126175051'
];
use Data::Dumper;
print Data::Dumper->Dump([$lwparg],['lwparg']);
$webpage = $browser->post($form_url, $lwparg, Content_Type => 'form-da
+ta'));

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Then you can test out variants of lwparg until you get one that's passing the right stuff.
--
@/=map{[/./g]}qw/.h_nJ Xapou cets krht ele_ r_ra/;
map{y/X_/\n /;print}map{pop@$_}@/for@/

[download]

In reply to Re: Using LWP's "post" to send n fields into a form? by fizbin
in thread Using LWP's "post" to send n fields into a form? by aboyd

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