First of all let’s say that regarding these functions what is valid for styles is exactly valid for scripts, but there are some exceptions to the contrary explained in the answer. Main difference between wp_enqueue_* and respective wp_register_* functions, is that the first adds scripts/styles to the queue, the second prepares scripts/styles to be added. … Read more
There is a function called wp_script_is( $handle, $list ). $list can be one of: ‘registered’ — was registered through wp_register_script() ‘queue’ — was enqueued through wp_enqueue_script() ‘done’ — has been printed ‘to_do’ — will be printed Ditto all that for wp_style_is().
Why registering and queuing properly matters it should be in time – earlier than script/style is up for being output to page, otherwise it is too late; it should be conditional – otherwise you are loading stuff where you don’t need it and cause performance and functionality issues, for this you need WP environment loaded … Read more
I found an other way that works well for me: When initializing the plugin, do not enqueue your scripts and styles, but register them with wp_register_style and wp_register_script. Next you can load the script/style on demand. For example when you render a shortcode with wp_enqueue_style(“your_style”) and wp_enqueue_script(“your_script”). Here is an example plugin using this method … Read more