{"id":2271,"date":"2019-06-29T12:23:45","date_gmt":"2019-06-29T11:23:45","guid":{"rendered":"https:\/\/www.nathankowald.com\/blog\/?p=2271"},"modified":"2022-03-08T23:52:44","modified_gmt":"2022-03-08T23:52:44","slug":"wordpress-shortcode-if-elseif-else-statements","status":"publish","type":"post","link":"https:\/\/www.nathankowald.com\/blog\/2019\/06\/wordpress-shortcode-if-elseif-else-statements\/","title":{"rendered":"WordPress shortcode: if-elseif-else statements"},"content":{"rendered":"\r\n

I found a great post<\/a> which shows how to easily use an if-else shortcode in WordPress.<\/p>\r\n\r\n\r\n\r\n

[if is_user_logged_in]\r\n    You are already logged in.\r\n[else]\r\n    Display registration form.\r\n[\/if]<\/pre>\r\n\r\n\r\n\r\n
A callable<\/a> must be used in the [if] condition.<\/p>\r\n
In the above example, is_user_logged_in<\/a> is the callable. This is a built in WordPress function to check whether the current visitor is a logged in user. It’s a shortcode equivalent of this PHP code:<\/p>\r\n
<?php
if ( is_user_logged_in() ) {\r\n    echo \"You are already logged in.\";\r\n} else {\r\n    echo \"Display registration form.\";\r\n}\r\n<\/pre>\r\n
The callable you use will likely be the name of a WordPress function, or function added by a plugin. It can also be an object<\/span> method or a static class method.

Callables support parameters, just like functions.<\/p>\r\n\r\n\r\n\r\n
[if is_singular book]\r\n    Show related books\r\n[\/if]\r\n<\/pre>\r\n\r\n\r\n\r\n
What if you need to check more than one condition?<\/h2>\r\n\r\n\r\n\r\n
I needed to check two<\/em> conditions:
1. Is user a “Member”
2. Is user logged in to WordPress<\/p>\r\n\r\n\r\n\r\n
I needed support for if-elseif-else statements.<\/strong><\/p>\r\n\r\n\r\n\r\n
If a user was a member<\/em>\u00a0I needed to show, “You are already a member”.
If a user<\/em> was logged in, I needed to show a signup form. 
Otherwise, I needed to show a different<\/em>\u00a0signup form.<\/p>\r\n\r\n\r\n\r\n
I modified the code in the article above and found a solution for doing if-elseif-else conditions.<\/p>\r\n\r\n\r\n\r\n
I changed the code to return a string (error message) instead of an Exception. A thrown Exception will not allow you to access the WordPress editor, if a non-callable is used in the shortcode. We need access to the editor to resolve this.<\/p>\r\n\r\n\r\n\r\n
Install the plugin<\/h4>\r\n\r\n\r\n\r\n
Clone the repo<\/a> to your \/wp-content\/plugins\/<\/strong> folder and the activate the plugin.<\/p>\r\n\r\n\r\n\r\n
git clone https:\/\/github.com\/n8kowald\/if-elseif-else-shortcode<\/pre>\r\n\r\n\r\n\r\n
This allows you to use the following shortcode:<\/p>\r\n\r\n\r\n\r\n
[if is_admin]\r\n    Hi God, you're up late\r\n[elseif is_user_logged_in]\r\n    Hi Zero Cool, welcome back\r\n[else]\r\n    Welcome to the website. Please register to continue.\r\n[\/if]<\/pre>\r\n\r\n\r\n\r\n
We can use multiple elseif<\/strong> statements for an unlimited amount of conditions.<\/p>\r\n\r\n\r\n\r\n
[if is_admin]\r\n    Hi Mr The Plague.\r\n[elseif is_user_logged_in]\r\n    Hi Zero Cool, hack the planet!\r\n[elseif is_single]\r\n   Pool on the roof must have a leak.\r\n[else]\r\n    Welcome an0n. Please look around but don't steal my fries.\r\n[\/if]<\/pre>\r\n\r\n\r\n\r\n
You can use if<\/strong> on its own<\/p>\r\n\r\n\r\n\r\n
[if is_admin]\r\n    Hi Mr The Plague.\r\n[\/if]<\/pre>\r\n\r\n\r\n\r\n
You can use if-else<\/strong> without the elseif<\/strong><\/p>\r\n\r\n\r\n\r\n
[if is_admin]\r\n    Hi Mr The Plague.\r\n[else]\r\n    Welcome an0n. Please look around but don't steal my fries.\r\n[\/if]<\/pre>\r\n\r\n\r\n\r\n
Allowed callables<\/h3>\r\n\r\n\r\n\r\n
The following callable functions are allowed by default:<\/p>\r\n\r\n\r\n\r\n
comments_open
get_field\r\nis_404\r\nis_admin\r\nis_archive\r\nis_author\r\nis_category\r\nis_day\r\nis_feed\r\nis_front_page\r\nis_home\r\nis_month\r\nis_page\r\nis_search\r\nis_single\r\nis_singular\r\nis_sticky\r\nis_super_admin\r\nis_tag\r\nis_tax\r\nis_time\r\nis_user_logged_in\r\nis_year\r\npings_open<\/pre>\r\n\r\n\r\n\r\n
Adding callables<\/h2>\r\n\r\n\r\n\r\n
To allow other callables you must use the if_elseif_else_shortcode_allowed_callables<\/strong> filter.

This “allow other functions” filter should be added to wherever you put your hooks<\/a>. That could be in:<\/p>\r\n