How to create a custom insert tags for Contao

The Contao cms supports dynamic content integration through the so called "insert-tags". Contao has a lot of built in "insert-tags" but sometimes when writing custom extensions may be the need to create a custom one.

Our custom “insert tags”

For the purpose of this tutorial we will create an extension for Contao that that provides two “insert tags” in order to display:

• The ip address of the visitor when called as {{mytag::ip_address}}
• The current page title when called as {{mytag::page_title}}

please note that the above functionalities are provided by the default {{env::ip}} and {{env::page_title}} “insert tags”.

Prepare the directory structure And files

Create the following files and directory under TL_ROOT/system/modules

[D]: directory - [F]: file
----------------------------------------------
[D] my_inserttags/
        [D] config/
                [F] config.php
        [F] MyInsertTags.php

Let’s start

Contao provides the insert-tags functionality through the replaceInsertTags hook, so the creation of a custom "insert tags" is a simple two step operation:

Step 1:

Put the following code into my_inserttags/config/config.php

<?php
$GLOBALS['TL_HOOKS']['replaceInsertTags'][] = array('MyInsertTags', 'outputTagContent');
?>

Step 2:

Put the following code into my_inserttags/MyInsertTags.php

<?php

class MyInsertTags extends Controller {
    
    
    public function outputTagContent($strTag) {
    
        /**
         * we need to run our function only if the $strTag argument is one of:
         * mytag::ip_address
         * or
         * mytag::page_title
         */
        
        $arrParts = explode('::', $strTag);
        
        /**
         * returning false means that our function can not recognize the tag
         * so Contao will try if the next hook applies
         */

        if ($arrParts[0] != 'mytag') {
            return false;
        }
        
        switch ($arrParts[1]) {
            
            case 'ip_address':
                
                /**
                 * here goes the code that match our mytag::ip_address tag
                 */
                
                return $this->Environment->ip;
            break;
            case 'page_title':

                /**
                 * here goes the code that match our mytag::page_title tag
                 */

                return $GLOBALS['objPage']->pageTitle;
            break;
        }
        
        /**
         * mytag::something is still an unrecognized tag
         */
        
        return false;
    }
}
?>

We are done

Our estension is ready to run. We can test it by creating a content element through the Contao backend and put the following lines in it:

You ip address is: {{mytag::ip_address}}

The page title is: {{mytag::page_title}}

If you have questions or comments do not hesitate to comment below.