循环时间段中的月份

<?php     $StartMonth   = '2014-08-12'; //开始日期    $EndMonth     = '2015-10-20'; //结束日期    $ToStartMonth = strtotime( $StartMonth ); //转换一下    $ToEndMonth   = strtotime( $EndMonth ); //一样转换一下    $i            = false; //开始标示    while( $ToStartMonth < $ToEndMonth ) {      $NewMonth = !$i ? date('Y-m', strtotime('+0 Month', $ToStartMonth)) : date('Y-m', strtotime('+1 Month', $ToStartMonth));      $ToStartMonth = strtotime( $NewMonth );      $i = true;      echo $NewMonth, '';    }    ?>