How Do I Create a Custom Validation in WordPress?

Creating a custom validation in WordPress is fairly simple. You can find the validation code in the functions.php file of your theme.

All you need to do is add the code to the functions.php file and define the validation function.

The validation function must take two arguments: the post object and the error message. The post object is the object you created when you created the post in WordPress.

The error message is the error message that you want WordPress to display when the validation fails.

Here is an example of a custom validation function that checks the title of a post to make sure it is between two specific lengths:

function title_validate( $post, $error_message ) { if ( strlen( $post->title ) < 200 || strlen( $post->title ) > 3000 ) { $error_message = “Title must be between 200 and 3000 characters long”; } }

When you define the validation function, you need to include the wp_check_validate_title() function. This function takes the post object as an argument and returns true or false.

If the validation function fails, WordPress will display the error message in the comments section of the post.

Here is an example of the code that you would add to the functions.php file to implement the title_validate() function:

add_action( ‘wp_check_validate_title’, ‘title_validate’ ); function title_validate( $post, $error_message ) { if ( wp_check_validate_title( $post, $error_message ) ) { return true; } }

Conclusion

Creating a custom validation in WordPress is easy. Just add the code to the functions.

php file of your theme and define the validation function. If the validation function fails, WordPress will display the error message in the comments section of the post.