How to create a monthly calendar with PHP

The example below allows you to create a simple monthly calendar using PHP. You can highlight the individual days of the month with different colors.

<style type="text/css">
	table  {
		border:1px solid #aaa;
		border-collapse:collapse;
		background-color:#fff;
		font-family: Verdana;
		font-size:12px;
	}
	
	th {
		background-color:#777;
		color:#fff;
		height:32px;
	}
	
	td {
		border:1px solid #ccc;
		height:32px;
		width:32px;
		text-align:center;
	}
	
	td.red {
		color:red;
	}
	
	td.bg-yellow {
		background-color:#ffffe0;
	}
	
	td.bg-orange {
		background-color:#ffa500;
	}
	
	td.bg-green {
		background-color:#90ee90;
	}
	
	td.bg-white {
		background-color:#fff;
	}
	
	td.bg-blue {
		background-color:#add8e6;
	}
	
	a {
		color: #333;
		text-decoration:none;
		
	}
</style>


<table border='0' >
<?php 
// Get the current date
$date = getdate();

// Get the value of day, month, year
$mday = $date['mday'];
$mon = $date['mon'];
$wday = $date['wday'];
$month = $date['month'];
$year = $date['year'];


$dayCount = $wday;
$day = $mday;

while($day > 0) {
	$days[$day--] = $dayCount--;
	if($dayCount < 0)
		$dayCount = 6;
}

$dayCount = $wday;
$day = $mday;

if(checkdate($mon,31,$year))
	$lastDay = 31;
elseif(checkdate($mon,30,$year))
	$lastDay = 30;
elseif(checkdate($mon,29,$year))
	$lastDay = 29;
elseif(checkdate($mon,28,$year))
	$lastDay = 28;

while($day <= $lastDay) {
	$days[$day++] = $dayCount++;
	if($dayCount > 6)
		$dayCount = 0;
}	

// Days to highlight
$day_to_highlight = array(8, 9, 10, 11, 12, 22,23,24,25,26);

echo("<tr>");
echo("<th colspan='7' align='center'>$month $year</th>");
echo("</tr>");
echo("<tr>");
	echo("<td class='red bg-yellow'>Sun</td>");
	echo("<td class='bg-yellow'>Mon</td>");
	echo("<td class='bg-yellow'>Tue</td>");
	echo("<td class='bg-yellow'>Wed</td>");
	echo("<td class='bg-yellow'>Thu</td>");
	echo("<td class='bg-yellow'>Fri</td>");
	echo("<td class='bg-yellow'>Sat</td>");
echo("</tr>");

$startDay = 0;
$d = $days[1];

echo("<tr>");
while($startDay < $d) {
	echo("<td></td>");
	$startDay++;
}

for ($d=1;$d<=$lastDay;$d++) {
	if (in_array( $d, $day_to_highlight))
		$bg = "bg-green";
	else
		$bg = "bg-white";
	// Highlights the current day	
	if($d == $mday)
		echo("<td class='bg-blue'><a href='#' title='Detail of day'>$d</a></td>");
	else 
		echo("<td class='$bg'><a href='#' title='Detail of day'>$d</a></td>");


	$startDay++;
	if($startDay > 6 && $d < $lastDay){
		$startDay = 0;
		echo("</tr>");
		echo("<tr>");
	}
}
echo("</tr>");
?>
</table>

Here is the result of the example: