php日历上一个按钮不断递增

Question

"Thank you I have already solved my problem I think this one work"

I have a code that display only mondays of the month.

The next button is not calculating well.

Supposed to be it well end on 12(Month).

But it continuously adding the month.

This is my PHP code.

<?php


$current_month = date("n");
$month = ($_GET['m']) ? $_GET['m'] : date("n");


$previous_month = ($month - 1);

$next_month = ($month + 1);

$year = ($_GET['y']) ? $_GET['y'] : date("Y");
$previous_year = $year;

if($month == 0)
{
  $month = 12;
  $year--;
}

if($month == 13)
{
  $month = 1;
  $year++;
}

if($previous_month == 0)
{
  $previous_month = 12;
  $previous_year--;
}

$startDate  = $year."-".$month."-01";
$endDate = $year."-".$month."-31";



$endDate = strtotime($endDate);
echo("<form name = 'formCalendar' id = 'formCalendar' action = 'calendar1.php?' method = 'get'>");
echo '<table border=1>';
echo '<tr>';
for($i = strtotime('Monday', strtotime($startDate)); $i <= $endDate; $i = strtotime('+1 week', $i))

    echo '<td>'.date('d-M-y', $i).'</td>';   

echo '</tr>';   
echo("        </select>");
echo("        <input type = 'button' name = 'prev' value = '<<' onclick = 'location=\"calendar1.php?m={$previous_month}&y={$previous_year}\"'/>");
echo("        <input type = 'button' name = 'next' value = '>>' onclick = 'location=\"calendar1.php?m=". ($month + 1)."&y={$year}\"'/>");
echo("  </table>");
echo("<form>");

?>

Pls help fix the problem.

Answer 1

here is your complete working code

<?php
$current_month = date("n");

$month = (isset($_GET['m'])) ? $_GET['m'] : date("n");
$year = (isset($_GET['y'])) ? $_GET['y'] : date("Y");

$previous_month = ($month - 1);
$next_month = ($month + 1);

$previous_year = $year;
$next_year = $year;

if($previous_month==0)
{
    $previous_month = 12;
    $previous_year = $year-1;
}

if($next_month>12)
{
    $next_month = 1;
    $next_year = $year+1;
}

$startDate  = $year."-".$month."-01";
$endDate = $year."-".$month."-31";        

$endDate = strtotime($endDate);
echo("<form name = 'formCalendar' id = 'formCalendar' action = 'calender1.php?' method = 'get'>");
echo '<table border=1>';
echo '<tr>';
for($i = strtotime('Monday', strtotime($startDate)); $i <= $endDate; $i = strtotime('+1 week', $i))

    echo '<td>'.date('d-M-y', $i).'</td>';   

echo '</tr>';   
echo("        </select>");
echo("        <input type = 'button' name = 'prev' value = '<<' onclick = 'location=\"calender1.php?m={$previous_month}&y={$previous_year}\"'/>");
echo("        <input type = 'button' name = 'next' value = '>>' onclick = 'location=\"calender1.php?m={$next_month}&y={$next_year}\"'/>");
echo("  </table>");
echo("<form>");
?>