last modified with php

it's nice to have your website say "last modified $date" with $date being the last time the page was, modified. this can be done in many ways, here are a few ways in perl, javascript and of course, PHP.

• javascript
• perl
• php

perl isn't bad but imho, the php way is much easier to understand. javascript is just plain nasty and would only be useful if you don't have access to a scripting language such as perl or php. if you don't know what 'a PHP' is then check out some easy-to-follow tutorials.

• How is daylight savings time taken into account?
• Would a clickable world imagemap be useful? Like, click on your desired part of the word and automagically have the correct timezone code. This may be done.
• Does this tutorial make sense? feedback is welcome.

let's do it

added timezone support to the tutorial. use this list of timezones to determine your proper last modified date. the examples demonstrate different timezones. I'm from Washington State so I use America/Los_Angeles for my zone.

i find the best way to learn is through examples. the code in the gray boxes is the exact code used while the bottom tan shows what the given php code outputs to the browser. the outputed date is, of course, the date the file was last modified.

make sense? it's fairly flexible. i don't suggest using the last one as it makes little sense but shows a point, although you are free to use it ;)

i have a little include file which i call: lastmodified.inc. i include this wherever I want to include the last modification date. so, here are the two parts. first, create a include file with your desired look. again, have a look at:

• the lastmodified.inc sourcecode
• timestamp using the above include timestamp and its source
• a test and its source (does NOT use lastmodifed.inc).
• list of timezones for your script.

of course you can delete the commented variable list. i find it's helpful to have during initial setup, especially when using a text editor. it's nice having it as an include somewhere though as changing the look and feel of the "Last Modified" date does happen, really it does.

But I want to check other files too!

You should notice the use of the getlastmod function, this checks the current file. If you want to check the last modification date of another file then replace it with a variable that calls on the filemtime and use it as such : $myfile = filemtime('/path/to/file/file.php'); and in the above examples/code change getlastmod() to $myfile and it will work for you.

date strings