javascript - Simple PHP form not working -

i´m trying make form works. i´m using codeigniter, view has form:

    <form class="renuncia_form" action="/formulario/send_form" method="post">         <p>             <label for="nombre">nombre y apellidos:</label>                 <input name="nombre" type="text" id="renuncia_nombre">             <br>             <label for="participe">nº partícipe: </label>                 <input name="participe" type="text" id="renuncia_participe">             <br>             <label for="nombre_fondo">nombre del fondo de inversión o sicav: </label>                 <input name="nombre_fondo" type="text" id="renuncia_fondo">             <br>             <label for="email">direccion de correo electrónico: </label>                 <input name="email" type="text" id="renuncia_email">             <br>             <input type="submit" value="enviar" class="renuncia_submit" name="enviar">         </p>      </form> 

and controller has php:

public function send_form(){     if($_post['submit'] == "submit")     {         $errormessage = "";          if(empty($_post['nombre']))         {             $errormessage .= "<li>you forgot enter name</li>";         }         if(empty($_post['participe']))         {             $errormessage .= "<li></li>";         }          $varmovie = $_post['nombre'];         $varname = $_post['participe'];          if(empty($errormessage))          {             $fs = fopen("mydata.csv","a");             fwrite($fs,$varname . ", " . $varmovie . "\n");             fclose($fs);              header("location: thankyou.html");             exit;         }     }  } 

i don´t know if i´m doing correctly form. want work normal form action, click on submit takes new page saying "thanks email", no ajax, that.

can me out one?

edit: put recipient e-mail?

 if($_post['submit'] == "submit") 

should

 if(isset($_post['enviar'])) 

as submit button not having name submit, instead name='enviar'