在当月的下拉列表中自动选择月份

I want to make my dropdown list auto select base on the present month and show the record on my datatable

        <div class="container-fluid">


    <h2 class="form-signin-heading">Schedule Management</h2><hr />
    <button class="btn btn-info" type="button" id="btn-add"> <span class="glyphicon glyphicon-pencil"></span> &nbsp; Add Schedule</button>
    <button class="btn btn-info" type="button" id="btn-view"> <span class="glyphicon glyphicon-eye-open"></span> &nbsp; View Schedule</button>
    <hr />

this part is where I select the month and submit(If i pick a month on my drop down ex.Nov it will auto submit its already working) what I want is to select automatically default value base on the present month ex. next month is Dec. everytime I open my website its already selected in Dec.

 (isset($_POST["months"])) ? $dropDownVal = $_POST["months"] : $dropDownVal=0;

   ?>
    <div class="content-loader">
           <form method="post" action="index.php">
 Select a month <select name="months"  id="months" onchange ='this.form.submit()'>
    <option value="0" <?php if ($dropDownVal==0) echo 'selected'; ?>>--------------</option>
    <option value="1" <?php if ($dropDownVal==1) echo 'selected'; ?>>January</option>
    <option value="2" <?php if ($dropDownVal==2) echo 'selected'; ?>>February</option>
    <option value="3" <?php if ($dropDownVal==3) echo 'selected'; ?>>March</option>
    <option value="4" <?php if ($dropDownVal==4) echo 'selected'; ?>>April</option>
    <option value="5" <?php if ($dropDownVal==5) echo 'selected'; ?>>May</option>
    <option value="6" <?php if ($dropDownVal==6) echo 'selected'; ?>>June</option>
    <option value="7" <?php if ($dropDownVal==7) echo 'selected'; ?>>July</option>
    <option value="8" <?php if ($dropDownVal==8) echo 'selected'; ?>>August</option>
    <option value="9" <?php if ($dropDownVal==9) echo 'selected'; ?>>September</option>
    <option value="10"<?php if ($dropDownVal==10) echo 'selected'; ?>>October</option>
    <option value="11"<?php if ($dropDownVal==11) echo 'selected';?>>November</option>
    <option value="12"<?php if ($dropDownVal==12) echo 'selected';?>>December</option>
</select>

<noscript><input type="submit" value="Submit"></noscript>

</form>
    <table cellspacing="0" width="100%" id="example" class="table table-striped table-hover table-responsive">

    <thead>
    <tr>
    <th>Sched #</th>
    <th>First Name</th>
    <th>Last Name</th>
    <th>Check In Date</th>
    <th>Check Out Date</th>
    <th>Room Rate</th>
    <th>Reservation Fee</th>
    <th>Date Paid</th>
    <th>Mode of Paymnet</th>
    <th>Status</th>
    <th>edit</th>
    <th>delete</th>

    </tr>
    </thead>
    <tbody>
    <?php
    require_once 'dbconfig.php';
    if(isset($_POST['months'])){ $months = $_POST['months']; }else { $months='';}
    $sqladd = mysql_query("SELECT sum(rrate) from tblguest WHERE status = 0 and MONTH(checkin) = '".$months."' ");
    while($result = mysql_fetch_assoc($sqladd)){
    $stmt = $db_con->prepare("SELECT * FROM tblguest WHERE status = 0 and MONTH(checkin) = '".$months."' ");
    $stmt->execute();
    while($row=$stmt->fetch(PDO::FETCH_ASSOC))
    {
        ?>
        <tr>
        <td><?php echo $row['id']; ?></td>
        <td><?php echo $row['fname']; ?></td>
        <td><?php echo $row['lname']; ?></td>
        <td><?php echo $row['checkin']; ?></td>
        <td><?php echo $row['checkout']; ?></td>
        <td><?php echo $row['rrate']; ?></td>
        <td><?php echo $row['reservefee']; ?></td>
        <td><?php echo $row['datepaid']; ?></td>
        <td><?php echo $row['modepayment']; ?></td>
        <td><?php echo $row['stats']; ?></td>
        <td align="center">
        <a id="<?php echo $row['id']; ?>" class="edit-link" href="#" title="Edit">
        <img src="edit.png" width="20px" />
        </a></td>
        <td align="center"><a id="<?php echo $row['id']; ?>" class="delete-link" href="#" title="Delete">
        <img src="delete.png" width="20px" />
        </a></td>
        </tr>
        <?php
    }  
    echo  "<b>Total Room Rental Income</b> = "  , $result['sum(rrate)'];
    }
    ?>




    </tbody>

Try this:

<?php

  $currentMonth = date('n');

?>

<select>

  <option value="1" <?php if ($currentMonth == 1) echo 'selected'; ?>>January</option>
  ...
  //up to december

</select>

Use this to check on date parameters of PHP.

http://php.net/manual/en/function.date.php