PHP Class – Calendar Matrix
by jandrews on Mar.08, 2010, under PHP Development
The other night I found myself needing a PHP class file that would give me calendar data. Specifically I needed something that I could build a calendar display with. The problem was I didn’t want it to write the HTML, I just wanted it to give me a multidimesional array of weeks and days. That way I could have whatever content I wanted in it. Not finding anything that didn’t write out HTML I created the CalendarMatrix class.
/**************************************************************************
Copyright 2010 James Andrews (email : contact at jamesmandrews dot com)
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation version 2 of the License
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
**************************************************************************/
class CalendarMatrix implements ArrayAccess, Iterator, Countable
{
// Define a list of the days of the week in english.
private $daysOfWeek = array( 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday','Saturday','Sunday');
private $dayCount = 0;
private $matix = array();
public function __construct($year, $month)
{
$this->dayCount = cal_days_in_month(CAL_GREGORIAN, $month, $year);
$this->generateMonthWeeksMatrix();
}
public function calendarDayHeaderArray()
{
return $this->daysOfWeek;
}
public function getMonthName($year=false, $month=false)
{
return date('F', mktime(0, 0, 0, $month, 1, $year));
}
private function firstDayOfMonth() {
return date("l", strtotime(date('m').'/01/'.date('Y').' 00:00:00'));
}
private function primeMatrix($startPos)
{
// Set up the first matrix array
$this->matrix[] = array();
for($count=0; $count < $startPos; $count++)
{
$this->matrix[(count($this->matrix)-1)][$count] = "";
}
return $matrixPos = count($this->matrix[(count($this->matrix)-1)]);
}
private function generateMonthWeeksMatrix()
{
// Get the position for the first day in the week header array.
$startPos = array_keys($this->daysOfWeek, $this->firstDayOfMonth());
// prime the matrix
$matrixPos = $this->primeMatrix($startPos[0]);
// Handle each day of the week
for($day = 0; $day < $this->dayCount; $day++)
{
// Fill in the date into the array value
$this->matrix[(count($this->matrix)-1)][] = ($day+1);
// If the current array hits a length of 7 start a new one.
if(count($this->matrix[(count($this->matrix)-1)]) == 7){
$this->matrix[] = array();
}
}
}
/*
* Below are our "implementataion functions."
*/
// We don't want to be able to change the data, so this
// function though here for compatibility does nothing.
// We'll throw an exception later.
public function offsetSet($offset, $value) {
}
public function offsetExists($offset) {
return isset($this->matrix[$offset]);
}
public function offsetUnset($offset) {
}
public function offsetGet($offset) {
return isset($this->matrix[$offset]) ? $this->matrix[$offset] : null;
}
public function rewind() {
reset($this->matrix);
}
public function current() {
return current($this->matrix);
}
public function key() {
return key($this->matrix);
}
public function next() {
return next($this->matrix);
}
public function valid() {
return $this->current() !== false;
}
public function count() {
return count($this->martrix);
}
}
The class is designed to mostly work like an array. With one exception, you can not modify an indexed value. It does how ever allow you to use for, and foreach statements to iterate through the array.
// Instantiate the matrix using the year and month in the constructor.
$matrix = new CalendarMatrix(2010, 03);
The matrix will now initialize itself with the constructor and you can use it like so.
<table>
<?php foreach($matrix as $week): ?>
<tr>
<?php foreach($week as $day): ?>
<td<>?php echo $day; ?></td>
<?php endforeach; ?>
</tr>
<?php endforeach; ?>
</table>
The code will now have created an calendar with the first row being Monday the last row being Sunday. There is also a function go build the day header at the top.
<table>
<tr>
<?php foreach($matrix->calendarDayHeaderArray() as $dayName): ?>
<th><?php echo $dayName; ?></th>
<?php endforeach; ?>
</tr>
<?php foreach($matrix as $week): ?>
<tr>
<?php foreach($week as $day): ?>
<td<>?php echo $day; ?></td>
<?php endforeach; ?>
</tr>
<?php endforeach; ?>
</table>
It is also flexible enough to be used to build a calendar out of divs simpley use both foreach calls next to each other and then put a div in the middle instead of a <td> tag.
