Sur le site d’une grande banque…

<script language="javascript">
function ifEnterIsPressed() {
    if (window.event.keyCode==13) {
        submitTheForm();
    }
}

function submitTheForm() {
    if ( (document.theform.password0.value.length >= 10) && (document.theform.password1.value.length >= 10) && (document.theform.password2.value.length >= 10) && (document.theform.password0.value.length <= 20) && (document.theform.password1.value.length <= 20) && (document.theform.password2.value.length <= 20) ) {
        document.theform.submit();
    }
    else {
        alert("Au moins un champs obligatoire est vide ou erroné.");
    }
}

</script>