Gdrcd 5.2 contatore caratteri azione in chat

<script language="javascript" type="text/javascript">

function Conta()
{
document.mex_chat.conta.value = document.mex_chat.message.value.length;
var massimo = 1500;
if (document.mex_chat.message.value.length > massimo)
{
alert("Massimo " + massimo + " caratteri!");
document.mex_chat.message.value = document.mex_chat.message.value.substr(0, massimo);
document.mex_chat.conta.value = massimo;
}
}

</script>

<div class="casella_chat">
<input id="message" value="" name="message" maxlength="1500/" onkeyup="Conta()"/>
<br/><span class="casella_info">
<?php echo gdrcd_filter('out',$MESSAGE['chat']['tag']['info']['msg']); ?>
</span>
<?php if($PARAMETERS['mode']['chatsave']=='ON'){ ?>
<span class="casella_info">
<a href="javascript:void(0);" onClick="window.open('chat_save.proc.php','Log','width=1,height=1,toolbar=no');">
Salva Chat
</a>
</span>
<?php } ?>
</div>

<!-- prova contatore-->

<div class="casella_chat">
<input class="conta" type="text" readonly="" value="0" name="conta">
<br>
<span class="casella_info"> Contatore </span>
</div>

<!-- fine prova-->
<div class="casella_chat">
<input type="submit" value="<?php echo gdrcd_filter('out',$MESSAGE['interface']['forms']['submit']); ?>" />
<input type="hidden" name="op" value="new_chat_message" />
</div>

document.mex_chat.conta.value

document.getElementById('conta').value

<script language="javascript" type="text/javascript">

function Conta()
{
document.getElementById('conta').value = document.getElementById('conta').value;
var massimo = 1500;
if (document.getElementById('conta').value > massimo)
{
alert("Massimo " + massimo + " caratteri!");
document.getElementById('conta').value = document.getElementById('conta').value(0, massimo);
document.getElementById('conta').value = massimo;
}
}

</script>

<script language="javascript" type="text/javascript">

function Conta()
{
document.getElementById('conta').value = document.getElementById('message').value.length;
var massimo = 1500;
if (document.getElementById('message').value.length > massimo)
{
alert("Massimo " + massimo + " caratteri!");
document.getElementById('message').value = document.getElementById('message').value.substr(0, massimo);
document.getElementById('conta').value = massimo;
}
}

</script>

<div class="casella_chat">
<input id="message" value="" name="message" maxlength="1500/" onkeyup="Conta()"/>
<br/><span class="casella_info">
<?php echo gdrcd_filter('out',$MESSAGE['chat']['tag']['info']['msg']); ?>
</span>
<?php if($PARAMETERS['mode']['chatsave']=='ON'){ ?>
<span class="casella_info">
<a href="javascript:void(0);" onClick="window.open('chat_save.proc.php','Log','width=1,height=1,toolbar=no');">
Salva Chat
</a>
</span>
<?php } ?>
</div>

<!-- prova contatore-->

<div class="casella_chat">
<input class="conta" id="conta" type="text" readonly="" value="0" name="conta">
<br>
<span class="casella_info"> Contatore </span>
</div>

<!-- fine prova-->
<div class="casella_chat">
<input type="submit" value="<?php echo gdrcd_filter('out',$MESSAGE['interface']['forms']['submit']); ?>" />
<input type="hidden" name="op" value="new_chat_message" />
</div>