How to Implement Conditional Logic in WordPress Plugin

Posted on 16th June 2023

If you’re developing a WordPress plugin, you may need to use conditional logic. That is, you’ll need to run certain code only if certain conditions are met. In this article, we’ll show you how to implement conditional logic in WordPress plugin.

Why Use Conditional Logic?

As we mentioned, conditional logic is used to run certain code only if certain conditions are met. For example, you may want to run a particular piece of code only if a user is logged in, or only if a certain post type exists.

Implementing conditional logic in your plugin can make it more flexible and adaptable to different WordPress installations. It can also help you avoid errors, as you can ensure that your code only runs when it’s supposed to.

How to Implement Conditional Logic in WordPress Plugin

There are two ways to implement conditional logic in WordPress plugin:

• Using the if statement
• Using the switch statement

We’ll show you both methods, so you can choose the one that’s best for your needs.

Using the if statement

The if statement is the most common way to implement conditional logic in PHP. It allows you to run a particular piece of code only if a certain condition is met.

For example, let’s say you want to run a piece of code only if a user is logged in. You would use the if statement like this:

if ( is_user_logged_in() ) {

// Code to run only if user is logged in

}

In the example above, we’re using the is_user_logged_in() function to check if a user is logged in. If the function returns true, that means the user is logged in, and the code inside the if statement will be executed.

If the user is not logged in, the code inside the if statement will not be executed.

You can also use the if statement to check multiple conditions. For example, let’s say you want to run a piece of code only if a user is logged in and if the user has the “administrator” role.

You would use the if statement like this:

if ( is_user_logged_in() && current_user_can( 'administrator' ) ) {

// Code to run only if user is logged in and has the "administrator" role

}

In the example above, we’re using the && operator to check two conditions. The code inside the if statement will be executed only if both conditions are met.

You can also use the || operator to check multiple conditions. For example, let’s say you want to run a piece of code if a user is logged in or if the user has the “administrator” role.

You would use the if statement like this:

if ( is_user_logged_in() || current_user_can( 'administrator' ) ) {

// Code to run if user is logged in or has the "administrator" role

}

In the example above, the code inside the if statement will be executed if either condition is met.

Using the switch statement

The switch statement is another way to implement conditional logic in PHP. It allows you to run a particular piece of code based on a certain value.

For example, let’s say you want to run a piece of code only if the current post type is “post”. You would use the switch statement like this:

switch ( get_post_type() ) {

case 'post':

// Code to run only if post type is "post"

break;

}

In the example above, we’re using the get_post_type() function to get the current post type. If the post type is “post”, the code inside the switch statement will be executed.

You can also use the switch statement to check multiple values. For example, let’s say you want to run a piece of code only if the current post type is “post” or “page”. You would use the switch statement like this:

switch ( get_post_type() ) {

case 'post':
case 'page':

// Code to run only if post type is "post" or "page"

break;

}

In the example above, we’re using the switch statement to check two values. If the post type is “post” or “page”, the code inside the switch statement will be executed.

Which Method Should You Use?

Both the if statement and the switch statement are valid ways to implement conditional logic in WordPress plugin. Which one you use is up to you and your needs.

If you need to check a single condition, then the if statement is the best option. If you need to check multiple conditions, then the switch statement is the best option.

In your plugin code, you can use the “if” statement to evaluate conditions. If the condition is met, the code block within the “if” statement will be executed. You can also use the “elseif” and “else” statements to add additional conditions.

Here is an example:

if ( condition ) {
// code to execute if condition is true
} elseif ( condition ) {
// code to execute if condition is true
} else {
// code to execute if condition is false
}

You can also use the “switch” statement to evaluate conditions. The “switch” statement will execute the code block associated with the first matching case. If no matching case is found, the code block associated with the “default” case will be executed.

Here is an example:

switch ( expression ) {
case label1:
// code to execute if expression = label1
break;
case label2:
// code to execute if expression = label2
break;
default:
// code to execute if expression is not equal to label1 or label2
}