PHP函数strtotime的扩展

function add_month ( $base_time = null, $months = 1 ) { if ( is_null ( $base_time ) ) $base_time = time(); $x_months_to_the_future = strtotime ( "+" . $months . " months", $base_time ); $month_before = ( int ) date ( "m", $base_time ) + 12 * ( int ) date ( "Y", $base_time ); $month_after = ( int ) date ( "m", $x_months_to_the_future ) + 12 * ( int ) date ( "Y", $x_months_to_the_future ); if ( $month_after > $months + $month_before ) { $x_months_to_the_future = strtotime ( date ( "Ym01His", $x_months_to_the_future ) . " -1 day" ); } return $x_months_to_the_future; }