how to submit a form to another page in wordpress plugin

Wordpress has a generic handler to deal with all forms - admin-post.php.

If you include a hidden field in your form called action, you can then hook in to a function of your choice with all the goodness of wordpress included.

echo "<form action='".get_admin_url()."admin-post.php' method='post'>";    echo "<input type='hidden' name='action' value='submit-form' />";    echo "<input type='hidden' name='hide' value='$ques' />";    { Enter the rest of your first block of code from above here }echo "</form>";

And then in your functions.php file (or any other php file that you have included via functions.php), you can use this method.

add_action('admin_post_submit-form', '_handle_form_action'); // If the user is logged inadd_action('admin_post_nopriv_submit-form', '_handle_form_action'); // If the user in not logged infunction _handle_form_action(){    { Enter your second block of code from above here }}

I'm not sure if you require a redirect once you reach your desired destination, but that can be easily accounted for if you do.

And one final question - is this form on the front end, or in the admin area? Not that it should make a difference that this answer, I'm just curious...

Your frontend_poll_process.php page is getting called out of the WordPress environment, therefore returning an error on $wpdb->get_results().

You can add your code to a plugin or functions.php using hooks:

<?phpadd_action( 'after_setup_theme', 'so_19997913' ); function so_19997913() {  require_once("function_ip.php");  $vote_result = $_POST['ans_name'];  $uid = uniqid();  global $wpdb;  $table_vote = $wpdb->prefix . "poll_answer_result";  $count = count( $vote_result );  $hidden = $_POST['hide'];  $ans_data = $wpdb->get_results( "SELECT  * FROM $table_vote WHERE question_id='$hidden'" );  if ( $count > 0 ) {    foreach ( $vote_result as $vote_arr ) {      $wpdb->insert( $table_vote, array('answer_id' => $vote_arr,        'ip' => get_client_ip(),        'question_uid' => $hidden      ) );    }  }}