Using strtotime with PHP

The strtotime() function in PHP allows you to convert English text date time strings into UNIX timestamps. It is useful for converting database datetime strings into UNIX timestamps and also creating dates into the future or past based on the current time or relative to a date and time in the future or the past. This post looks at some examples of doing this.

Categories PHP

Get unique array values with PHP

The PHP function array_unique() allows you to create a new array which contains only the unique values from the original array. This post looks at some examples of using the array_unique function.

Categories PHP

Assigning values to associative arrays in Javascript

Javascript has zero indexed integer arrays and also associative arrays. They work in a similar manner but there is a useful way to be able to initialise an associative array with both keys and values in one call. This post will look at the way a zero based integer based array can be initialised and then the ways it can be done with associative arrays in Javascript.

Splitting a large Apache log file with PHP

A little while back I needed to split a large Apache log file (3.5GB) up into smaller pieces and wanted to break it up into several files, with one for each day of the month. I initially tried using "grep" on the command line but this proved to be too slow, and I needed to run it once for each day and month so it was going to take 92 times to run, extracting just one day at a time over the course of three months. I ended up writing a quick little PHP script which was able to split the 3.5GB file into 92 files, one for each day of each month in under 4 minutes.

 

Categories PHP

Using Javascript to focus a form element onload

The Personalised Plates website has a big input box on every page for searching for available personalised plates. The page template uses the Javascript form element focus() function to set the focus on this text box when the page loads so the user can start to type in a personalised plate idea without having to click the box with their mouse.

PHP error Call to undefined function ImageCreateFromPNG

If you get the following error message in PHP then it means you need to have the PHP GD extension installed. Obviously the /path/to/file.php will be the actual path and filename of the PHP script the error occured in, and the line number will be the actual line.

Fatal error: Call to undefined function ImageCreateFromPNG() 
  in /path/to/file.php on line 379

You’ll also get this error message using other functions such as ImageCreateFromJPEG() if the PHP GD library is not installed.

Categories PHP