Disemvoweling PHP Function

7th April 2009 - 2 minutes read time

Note: This post is over a year old and so the information contained here might be out of date. If you do spot something please leave a comment and we will endeavour to correct.

Disemvoweling is a technique used on blogs and forums to censor any post or comment that contains spam or other unwanted text. It involves simply removing the vowels from the text so that it is almost, but not entirely, unreadable.

Use the following function to disemvowel a string of text.

function disemvowel($string)
{
    return str_replace(array('a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U'), '', $string);
}

As an example, the first sentence on this post:

Disemvoweling is a technique used on blogs and forums to censor any post or comment that contains spam or other unwanted text.

would appear like this:

Dsmvwlng s tchnq sd n blgs nd frms t cnsr ny pst r cmmnt tht cntns spm r thr nwntd txt.

Which doesn't make a lot of sense, but is still kind of readable. This technique kills unwanted comments without removing the text entirely.

Check out the Wikipedia page on Disemvoweling for more information on the origins or this method.

PHP

Comments

Permalink

Never seen this before, but is very interesting

Permalink

how do u disemvowel someone's comment like say facebook. It's a perfect argument ender.

Permalink

Nice tool. Wonder if it would make sense to only apply the replacement to words that are larger than 3 characters.

Add new comment

Related Content

Run PHP Through A Browser With PHPSandbox

I use sites like CodePen and JSFiddle all the time to write JavaScript and CSS, but I've not seen a similar site for writing PHP applications. I have used 3v4l.org to test small scripts using different versions of PHP, but it doesn't allow dependencies to be added and doesn't have a nice editing interface.

Recently, I found a site called PHPSandbox that allows users to create PHP applications that can be run in the same way as applications on CodePen. This includes using composer to inject dependencies into the application and a nice little editor interface to see the output and logs from the application.

Fibers In PHP 8.1

PHP 8.1 comes with a few new additions to the language, and one that I have seen get the most attention is fibers. This is a feature that allows PHP code to be executed in a concurrent thread, with the ability to pause and resume that code at will.

Using fibers doesn't mean that the code runs in parallel, rather that the code is executed away from the main thread in a virtual or green thread. These are threads create by and executed by the PHP VM, rather than being executed by the CPU and managed by the underlying OS. This lightweight thread of execution is also called a coroutine and are executed in sequence, rather than being parallel.

Fibers are intended to eliminate the distinction between synchronous and asynchronous functions in PHP and provide a petter mechanism to manage blocking code.

Debugging And Testing PHP With assert()

PHP has a built in debugging and testing tool called assertions, which is essentially the assert() function and a few configuration options.

With this feature you can add additional checks to your application whilst you are developing it so that when you deploy to production you can be sure that things will run correctly. It is simple to run and allows you to embed testing code within your production code without having an adverse effect on performance.

I've seen the use of assert() in a couple of open source PHP projects, but had not really dug into how it works or what it does. As it turns out, assert() is actually very useful and can also be found in other languages like C/C++, Python and JavaScript.

Installing SimpleSAMLphp Using Composer

Security Assertion Markup Language (SAML) is a standard that passes authentication credentials between hosts and essentially allows for a single sign on solution to be created. The standard uses XML files that get passed between the authentication system (known as the identity provider or IdP) and the service users want to sign into (known as the service provider or SP).

SimpleSAMLphp is an open source application that implements SAML mechanisms and allows for the authentication system to be created as well as some administration tasks to be performed. The system is robust and battle tested, having been integral to the open source authentication systems for a number of years.

Create Checksums Using The Luhn Algorithm In PHP

The Luhn algorithm was created by Hans Peter Luhn and is a way of creating a simple checksum for a number. This algorithm, also known as the mod 10 algorithm, is used in a wide variety of applications but is commonly associated with credit card numbers.

If you look at the numbers on the front of your credit card the last digit on the right is the checksum. An algorithm is done on the other numbers and if the checksum is the same then the number is considered valid.

Outside of credit card numbers, the Luhn algorithm can be used to create a checksum on any number that you want to store. It is especially handy when you want to give users a number that they will be hand typing into a computer. The checksum helps spot any errors in typing in the number before that number is processed. The good thing about the Luhn algorithm is that it doesn't matter how long the number is so it will work with any kind of digit sequence.

Swapping Between Different Composer Versions

I had an issue I was trying to debug today and needed a way to swap between different versions of composer. Composer is one of the few things that I install globally so it was locked at a particular version on the machine I was using. There has been some significant changes between version 1 and version 2 and it isn't quite safe to use a composer 2 package on a platform that has composer 1 installed. As some projects I'm working on haven't been upgraded yet I needed a way to swap between versions whilst this work was being done.