Using regular expressions to extract content

PHP provides a number of really neat regular expression functions. You can find the list of the regex function at the PHP site.
But the one that I’ve had most fun with is the preg_match_all() function which I’ve been using to do content extraction from an HTML page.

Posted on April 22, 2008 at 7:03 pm by Eldee · Permalink · 16 Comments
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Parsing a URL querystring into variables in PHP

It’s common knowledge you can read variable from a URL querystring by using $_GET array in PHP, but that’s only possible if the URL is “executed” in the browser.
For those who might not know, querystrings are those variable-value pairs that appears behind ‘?’ of a URL. For example,
http://www.mysite.com/index.php?variable1=1&variable2=1
gives the querystring “variable1=1&variable2=1″.
What happens if [...]

Posted on April 17, 2008 at 4:16 pm by Eldee · Permalink · One Comment
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Checking a string is alphanumeric in PHP

There may be times when you need a way to check that a string only contains alpha-numeric characters. That means only alphabets A-Z and numbers 0-9.
Most PHP-ers will probably use regular expressions and the function preg_match(). I will admit that regular expressions is really powerful, but it’s a real pain to learn and master. Fortunately [...]

Posted on April 11, 2008 at 4:18 pm by Eldee · Permalink · 10 Comments
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PHP Operators: Assignment

The main assignment operator is ‘=’, which basically assigns a value on the right to a variable on the left. If you think this is the same as an equal sign in mathematics, don’t! Think of it as a ‘assigned to’ so whatever is on the right is assigned to the left.
Here’s a simple [...]

Posted on February 11, 2008 at 4:58 pm by Eldee · Permalink · Leave a comment
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PHP Operators: Maths

There are various kinds of operators used in PHP, but we’re going to start with the most basic and commonly known operator – the Math operators.
What are operators? They are basically a special set of characters (or symbols, if you like) which tells PHP to perform a certain operation. For example, the ‘+’ (plus sign) [...]

Posted on January 31, 2008 at 5:32 pm by Eldee · Permalink · Leave a comment
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Using comments in your PHP scripts

Adding comments to PHP code is a very useful practice. Comments allows you to add some descriptive text that you can use to document or remind you on what the various parts of the PHP script is doing.
Comments are not sent to the browser, so it won’t be visible in the actual page you load [...]

Posted on January 23, 2008 at 3:47 pm by Eldee · Permalink · Leave a comment
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