Page 9 of Software Development Articles

Simple Probability Distribution with PHP

We’ve all been there, trying to juggle two or more things for either split testing or just because you want some variety. This came up recently for me with juggling advertising networks and I wrote some simply code to handle it. The premise is simple, you assign weights to the […]

Incrementing / Decrementing a Number by a Number with PHP

We’ve previously discussed how to simply increment and decrement a variable but that only covered incrementing by a value of 1. What about when you want to increment a variable by 5s? There’s a few different ways this can be accomplished. First, the obvious (albeit far from ideal) using ++ […]

The Complexity of Permalinks and Slugs with User Generated Content

I’m not referring to the complexity of the permalink or slug itself, but the complexity to your code that can be introduced with certain formats, specifcally anything that the user can modify. When I was originally building SceneKids.com I wanted to ensure that the user’s username was always in the […]

Sorting an associative array by a specific key with PHP

One of PHP’s most powerful data types is the array. It can hold numbers, it can hold letters, it can be sorted, sliced and chunked. Speaking of sorting, when sorting an array the straight forward sorting functions are only for sorting by the keys or by the values. What about […]

How to convert a CSV file into an array with PHP

Loading CSV files into an array is something that comes up more times than I’d like to admit. Scrubbing mailing lists, loading flat files to a database and various other use cases are out there and fortunately, PHP makes it easy to to do. There are a few ways to […]

How to Determine if it is Friday the 13th with PHP

It seemed fitting that my post on Friday the 13th would be about Friday the 13th. There are 52 Fridays in 2013, but only 2 of them are the 13th day of the month (September and December). To determine if a Friday is a Friday the 13th, we will need […]

Building a Number Guessing Game in PHP

Believe it or not, but the last 13 or so posts have all been leading up to this one. Generating random numbers, capturing user input, using colors on the command-line, pluralizing words, and then some are all being utilized in this simple number guessing game. The script itself generates a […]

How to Terminate a PHP Script

Terminating the execution of a script is usually one of those last ditch ways to handle an error, but it is something we do from time to time, especially if we’re debugging. To terminate the execution of a script, you can call either exit or die, die being an alias […]

How to Pluralize Words with PHP

There’s a good chance you’ve seen it before (and possibly authored it), it looks something like this “You have 1 new messages” or “There are 10 user(s) logged in”. What you end up with is something that’s either incorrect or something like looks a bit amateurish. To fix this, we […]

How to Output Variables within Strings with PHP

Displaying strings isn’t that hard, you just use echo followed by the string in question. But that only gets us so far, what about when we need to use variables inside of the string? Luckily there’s a ton of different ways to accomplish this. echo You can easily use echo […]

Why Limit the Format of a Password?

I’ve been moving towards using longer and longer passwords. When I say longer, I mean upwards of over 20 characters, mixed case, numbers and special characters. These longer passwords make me feel a bit more secure, especially when I can also leverage two-factor authentication on top of it. Know what […]

How to Use Colors in Command-line PHP Output

Nothing spruces up command-line output the way colors do. Just like when you’re customizing your [Bash] prompt, you can use color codes in strings to colorize your output. Keep in mind, these colors will only work on the command-line and not in a browser. First let’s take a look at […]

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 […]

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 * […]