Custom Tags
 

I'm trying to figure out how to write custom tags.

What I want to do is make a tag

card
/card

and a person could put the card name within the tag and it would pull up the info on that card in a pop up. the card info would be coming from my online store.

If by tag you mean "BB Code" (something like [card] [/card] ) you make that with the BB Code Manager in your Admin CP, "Add a New BB Code."

You need to put in "Replacement HTML" - that is the HTML code vbulletin will insert when it finds the BB Code tags in a post. Inside the the replacement HTML you use {param} to put whatever info you put between the tags into the HTML... so if you call cards by id number say you would use your tag like [card]1013[/card] and somewhere in the HTML you can add the "1013." If you have 2 custom fields you can make a BB Code with an option, in which case you'd call the card with something like [card="white"]1013[/card] and use {option} in the HTML replacement to insert "white" in this example.

It may be a little hard to explain but it's really very easy- I suggest going to the mods section and looking at some of the BB Codes so you can see how it works.