Date/Time Processing with PHP - Turning The Tables

(Page 7 of 7 )

Now, let's get into the display() method, which takes care of actually printing the calendar. There's one important thing needed here: the day of the week on which the first of the month falls.

<?
// find out which day the first of the month falls on
$firstDayOfMonth = date("w", mktime(0, 0, 0,
$this->currMonth, 1, $this->currYear));
?>

The first day of the month (from the $firstDayOfMonth variable) and the last day (from the $totalDays array) provide the bounding values for the month view I'm going to be building.

I'll explain how this view is constructed row by row. The first row contains just the name of the current month.

<?
// header
echo "<tr>\n";
echo "<td colspan=7 align=center><font face=Arial
size=-1><b>" . $this->months[$this->currMonth] . " " . $this->currYear .
"</b></font></td>\n";
echo "</tr>\n";
?>

The next row contains seven cells, one for each day of the week - I've used the substr() function to display the first three letters of each day name from the $days array.

<?
// day names
echo "<tr>\n";
for ($x=0; $x<7; $x++)
{ 
echo "<td><font face=Arial size=-2>" .
substr($this->days[$x],0,3) . "</font></td>\n"; 
}
echo "</tr>\n";
?>

The next few rows are all generated automatically. The first order of business is to place the first day of the month on the corresponding day. Since I already have a $firstDayOfMonth variable, I've used a simple loop to fill all the cells prior to that day with non-breaking spaces.

<?
// start printing dates
echo "<tr>\n";
// display blank spaces until the first day of the month
for ($x=1; $x<=$firstDayOfMonth; $x++)
{
// this comes in handy to find the end of each 7-day block
$rowCount++;
echo "<td><font face=Arial
size=-2>&nbsp;</font></td>\n";
}
?>

The $rowCount variable is simultaneously keeping track of the number of slots (cells) being filled up - I'll use this a little further down to determine when the end of the week has been reached.

Once the first day of the month is determined, another "for" loop (iterating from 1 to the number of days in the month) is used to generate the remaining rows and cells of the table. The $rowCount and $dayCount variables are incremented at each stage, and the $rowCount variable is divided by 7 to find out when the seven slots available in each row are filled up.

<?
// counter to track the current date
$dayCount=1;
while ($dayCount <= $this->totalDays[$this->currMonth])
{
// use this to find out when the 7-day block is complete and display a new row
if ($rowCount % 7 == 0)
{
echo "</tr>\n<tr>\n";
}
// print date
// if today, display in different colour
if ($dayCount == date("j") && $this->currYear == date("Y")
&& $this->currMonth == date("n"))
{
echo "<td align=center bgcolor=Silver><font face=Arial size=-1>$dayCount</font>";
}
else
{
echo "<td align=center><font face=Arial size=-1>$dayCount</font>";
}
echo "</td>\n";
// increment counters
$dayCount++;
$rowCount++;
}
echo "</tr>\n";
echo "</table>\n";
}
?>

Notice that I've inserted an "if" statement into the loop to display the current date in a different colour, if a match is found.

Here's an example of how this class might be used:

<?
include("Calendar.inc");
$cal = new Calendar(2002, 12);
$cal->display();
?>

And here's what it would look like:



Pretty cool, huh?

This is just one example of the myriad uses to which PHP's date functions can be put. There are many more; I'll leave them to your imagination. Until next time...be good! Note: All examples in this article have been tested on Linux/i586 with Apache 1.3.20 and PHP 4.1.1. Examples are illustrative only, and are not meant for a production environment. Melonfire provides no warranties or support for the source code described in this article. YMMV!

DISCLAIMER: The content provided in this article is not warranted or guaranteed by Developer Shed, Inc. The content provided is intended for entertainment and/or educational purposes in order to introduce to the reader key ideas, concepts, and/or product reviews. As such it is incumbent upon the reader to employ real-world tactics for security and implementation of best practices. We are not liable for any negative consequences that may result from implementing any information covered in our articles or tutorials. If this is a hardware review, it is not recommended to open and/or modify your hardware.

Comments On: Date/Time Processing with PHP

>>> Be the FIRST to comment on this article!