Drupal render results in block after posting form

Question

I have a form that is created in a block in drupal, what I would like to do is display a result of the calculated values passed to the form in the same block.

1. I render the form using

_block_view $blocks['content'] = drupal_render(drupal_get_form('form_name'));

1. the form is displayed
2. on form submit I do a calculation on the posted values
3. from here I want to display the result in the original block

How do I capture the result and display it, or ideally display it under the form retaining the forms values?

Answer 1

OK what I did was add $form_state ['redirect'] = FALSE; to the submit handler, and the form populated itself, I then added a new form field with a readonly attribute and set #value to the calculated value utilising the values passed back inside $form_state['input']... also I omitted drupal_render( from the $blocks['content']= setting call above as it was not required