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How to Compare Numeric Variables with PHP

Comparing numeric values is a very common programming task. Which number is greater? is lesser? equal? In PHP like any C-style language, you can do these comparisons with a simple if ( ... ) { ... } statement: if ($var1 > $var2) { echo $var1 . ' is greater than […]

How to check if a variable is an integer with PHP

PHP has a variety of functions and approaches to determine if a variable is a number and/or an integer. The problem is that many of the straight forward approaches can result in false positives depending on how they react to type juggling. Case in point, is_int() will return false for […]

Simplifying Single Server Deployments

Last week I discussed the importance of version control for individuals but something I didn’t touch on was how version control systems can be used to simplify and/or automate deployments. I’ve been through the different setups out there, using plain old rsync, leveraging GitHub’s Post-Receive WebHook to call a URL […]

How to Strip Whitespace from a String with PHP

Whitespace, it can make all the difference in the world when attempting to determine if a string is empty or not. Anytime you are working with user input I recommend stripping whitespace from both sides of the string. When stripping whitespace you can choose to strip from both sides or […]

How to Increment / Decrement a Number with PHP

Incrementing and decrementing a variable can be accomplished with C-style pre- and post-operators. The pre-operators return the value after it as been incremented or decremented, post- return the value before. Let’s take a look at incrementing first: $i = 1; echo ++$i; // outputs 2 echo $i++; // also outputs […]

While you were out - `while` loops in PHP

while loops are considered the simplest type of loop in PHP-dom. Their purpose is to continue to execute until a condition has been met. Let’s look at an example related to the title, a pseudo-script that will collect messages while you’re out, returning at 1pm (like a lunch break ;): […]

Version Control for Individuals

I find with a lot of folks I interact with, version control is considered something that you use when you are working on a team with multiple contributors. As an individual that is usually the sole contributor of my own projects, I have to disagree as version control is still […]

New Lines in Command-line PHP Output

If you’ve ever worked with command-line PHP and outputted text you know that PHP takes absolutely no liberties with injecting line breaks into the output. There’s also no magic function or configuration variable that will adjust this behavior. Easy enough, you want line breaks, just add them! echo "I am […]

How to Output Strings in PHP

Outputting strings is one of the most common actions when building a web site, and PHP offers a multitude of ways to do so each with their own set of strengths and weaknesses print print is a language construct and not a function, so you don’t need any parenthesis to […]

How to Capture User Input from Command-line PHP

When using command-line PHP capturing input is a bit different than when building a web application. Instead of building a form and interrogating some variables, you have to actually prompt the user for the input and then analyze it to determine if what the user input was what you were […]

The Importance of a Logout Page

Running social networks have proven eye opening in regard to how users interact with a website. One thing that I’ve noticed that I didn’t necessarily expect is that quite a few people click the logout button. Perhaps it’s because they have more than one account (tsk tsk as we don’t […]

How to Generate a Random Number with PHP

Generating a random number in PHP is very simple and like most things, can be done a number of different ways. The old standby is to use the function rand() to to generate a random integer between the minimum and maximum values that you provide. To generate a number between […]

Using Transactions with PHP Data Objects (PDO)

With PHP Data Objects, transactions are pretty simple. To be able to use a transaction, you simply wrap your queries with a call to beginTransaction() and either use commit() or rollBack() at the end. Rolling back is at your discretion but the easiest implementation would be to wrap the queries […]

How to Use Prepared Statements in PHP

Now that we know how to create a connection to our database using PHP Data Objects, let’s talk a bit about prepared statements. Now I’d like to think that we’ve all made this mistake before, taken user input and used it in an SQL query something like this: $db->execute('SELECT * […]

Yet Another Linode vs. DigitalOcean Post

This has been turning into an every 3 month thing since I originally blogged about Linode vs. DigitalOcean back in late February and then again about Linode NextGen vs. DigitalOcean in May. Not to mention when I moved out of the cloud in June when I switched to bare metal […]

How to Connect to a Database with PHP Data Objects (PDO)

PHP Data Objects (PDO) provide a consistent interface to different databases including MySQL, PostgreSQL, SQLite, SQL Server and a handful of other systems as well. Aside from database-specific SQL, the only other thing that isn’t consistent is how to connect to a database. Each database type requires a string to […]

Split a String by Letters with PHP

Every once in a blue moon you find yourself needing to take a string and converting it to an array of characters in the string. Maybe it’s because you want to count how often certain letters exist in the string or want to convert the letters to something else. To […]

Passing Arguments to Command-Line PHP

In a previous post we discussed how to tell whether or not you are on the command-line from within your PHP script. Today we’re going to talk about passing command-line arguments to your script. When on the command-line two variables are available to you, $argc and $argv. They are the […]

MySQL and Redis Command Equivalents

Score another one for HitTail as this particular topic was their suggestion. MySQL (PostgreSQL, SQL Server, SQLite or any other RDBMS I didn’t list) and Redis are completely different beasts in regard to syntax and especially schema design (or lack there of). The following are just some common SQL statements […]

Calculating page load time / execution time with PHP

So who remembers back in the day when one of the coolest things you could have on your website’s footer was the page load time? As passé as that may seem in this day in age, it’s still something that can be useful when attempting to profile a site or […]

Check if PHP is running from the command-line

When running PHP from the command-line interface, the availability of some variables and functionality may or may not be available. Case in point, when running command-line PHP sessions are not available and $_SESSION is undefined. When you’re on the command-line there’s also the possibility that you want to use the […]

Check if a PHP class exists

We’ve discussed how to check if a class has a function but what if the class doesn’t exist at all? To check if a class exists you can use, use guessed it, class_exists(). if (class_exists('MyClass')) { $object = new MyClass(); } else { throw new Exception('The class MyClass does not […]

WP Engine Review

Now that I’m back on the WordPress bandwagon and have been using WPEngine for a bit of time now, it’s time to talk about it. As previously discussed, I opted to use a hosted WordPress solution because of my utter disdain for administering WordPress. When researching WordPress hosts, I got […]

Check if a PHP class has a certain function

We’ve previously discussed how to check if a function exists but that only works on standalone functions like the ones built into PHP as well as any user defined functions. Luckily there’s a function for that called method_exists(). When speaking in the scope of a class, the functions are referred […]

Check if a PHP function exists

Let’s use json_encode as an example here. Prior to PHP 5.2.0 JSON support was only available via a PECL extension and since 5.2.0 it’s been available as part of the PHP core. You could check that the server is running PHP 5.2.0 or above, but that could result in a […]