Drupal Form:want to show previous form value as default_value on page

Question

My Goal is if user is submitting this form with \"Product Name\" value as \"YYY\". On submit page should reload but this time \"Product Name\" should show previous valye as

Answer 1

Not sure if this would work for you, but you could try adding the #default_value key to the form array

$form['productname'] = array (
'#type' => 'textfield',
'#title' => t('Product Name'),
'#required' => TRUE,
'#size' => '20',
'#default_value' => variable_get('productname', ''),
);

That way if the variable is set it will grab whatever it is, but if not you can use a default value.