<script language="javascript">
function Test(obj){
if(isdate(obj.value)){
alert("success");
return true;
}
alert("wrong");
}
function isdate(s)
{
var patrn=/^^((((1[6-9]|[2-9]/d)/d{2})-(0?[13578]|1[02])-(0?[1-9]|[12]/d|3[01]))|(((1[6-9]|[2-9]/d)/d{2})-(0?[13456789]|1[012])-(0?[1-9]|[12]/d|30))|(((1[6-9]|[2-9]/d)/d{2})-0?2-(0?[1-9]|1/d|2[0-8]))|(((1[6-9]|[2-9]/d)(0[48]|[2468][048]|[13579][26])|((16|[2468][048]|[3579][26])00))-0?2-29-))$/;
if (!patrn.exec(s)) return false ;
return true;
}
</script>
<form name="form1">
<input name="email" type="text" value="aaa" οnblur="Test(this)"/>
<input type="submit">
</form>