<form name="nom_form" action="page1.php" method="POST">
<input type=file name=fichier onKeyPress="nom_form.fichier.blur()">
<input type="text" name="truc">
<select name="listlist" onChange="nom_form.truc.value=nom_form.listlist.value">
<option value="1">truc
<option value="2">trucrtyh
<option value="3">truczer
</select>
</form>