how to handel a submitted value in drupal form - php

Question

I created a simple user form that allows the user to give a database name and when the user submitt the drupal site will be connected to the given databasename, I defined my database in the file settings.php: myDataBase and when I try
db_set_active('myDataBase');
it works fine but when I type myDataBase in the text field and submitt and then use the submitted value to connect to the database it didnt work.
<?php
function testform_menu() {
$items = array();
$items['test'] = array(
'title' => 'connect an external database',
'page callback' => 'drupal_get_form',
'page arguments' => array('testform'),
'access callback' => TRUE,
'type' => MENU_NORMAL_ITEM,
);
return $items;
}
function testform($form, &$form_state) {
$form = array();
$form['Databasename'] = array(
'#type' => 'textfield',
'#title' => t('enter the database name'),
'#description' => t('a user interface to switch between databases'),
'#size' => 28,
'#required' => TRUE,
);
$form['submit'] = array(
'#type' => 'submit',
'#value' => t('Submit'),
);
return $form;
}
function testform_validate($form, &$form_state) {
}
function testform_submit($form, &$form_state) {
if (db_set_active('myDataBase'))
{
drupal_set_message('database connected'); // works
}
// $database_name =$form_state['values']['Databasename']; // ius not working!!
// if ($database_name ) {
// db_set_active($database_name); // I even tried to parsing the submitted value to a string but didnt work in both case
// drupal_set_message(t('connected to the database'.' '.$database_name));
// }
db_set_active();
}

Answer 1

You need a function to manage your form submit, for example:
function testform_submit($form, &$form_state)
{
//Do your stuff
}
Or you can define the submit function using the #submit key in your form:
'#submit' => array('your_custom_function_name')
More info: https://api.drupal.org/api/drupal/developer!topics!forms_api_reference.html/7#submit_property
Inside this function you can process your form.