Formulaire contact

<form method="post" action="mail.php" enctype="multipart/form-data"><br>
<table width="100%" border="0" cellspacing="1" 

cellpadding="2"><br>
<tr> <br>
<td width="51%">Votre email :</td><br>
<td width="49%"> <br>
<div align="center"><br>

<input type="text" size="35" name="Email"><br>
</div><br>
</td><br>
</tr><br>
<tr> <br>

<td width="51%">Le sujet :</td><br>
<td width="49%"> <br>
<div align="center"><br>
<input type="text" size="35" name="Sujet"><br>

</div><br>
</td><br>
</tr><br>
<tr> <br>
<td width="51%">Votre message :</td><br>
<td width="49%"> <br>

<div align="center"><br>
<textarea cols="35" rows="5" name="Message"></textarea><br>
</div><br>
</td><br>

</tr><br>
<tr> <br>
<td colspan="2"> <br>
<div align="center"> <br>
<input type="submit" value="Envoyer" name="Envoyer"><br>

<input type="hidden" name="send" value="envoi"/><br>
</div><br>
</td><br>
</tr><br>
</table><br>

</form>

<?php
if($send =="envoi") 
{
if($Message =="") ( > si Message = rien )
{
echo("Le champ Message est vide !"); } 
elseif($Sujet =="")  {
echo("Le champ sujet est vide !");
}
elseif($Email =="") 
{
echo("Le champ email est vide !");
}
else
{
mail("monemail@domaine.com",$Sujet,$Message,"From: ".$Email); 
echo("Votre message a bien été envoyé");
}

}
?>