php中$_POST[]取不到值
<?php
include("mysql_class.php");
echo $_POST[name].a;
?>
<form action="" method="post">
<select name="name" >
<?php
$query=$db->query("select*from p_newsclass where f_id='0'");
while($row=$db->fetch_array($query)){
echo "<option value=\"$row[id]\">$row[name]</option>";
$query_fid=$db->query("select*from p_newsclass where f_id='$row[id]'");
while($row_fid=$db->fetch_array($query_fid)){
echo "<option value=\"$row_fid[id]\"> $row_fid[name]</option>";
}
}
?>
<option value="value1">option1</option>
</select>
</form>