Through My Lenses

What is a custom tags?

• CF custom tags are user created tags to extend the tag set
• written in CF
• executed on CF server
• used along side standards tags
• locally available

Why use them?

• code reuse
• encapsulation
• abstraction
• simplification
• customized control flow
• packaging

What about CFC?

• yes everything you can do everything in CFCs but sometimes cust tags can sometimes offer a more natural feeling

Basics

• stored anywhere the server has access to
• invoking: cf_, cfModule, cfImport
• execution: open, close, self-close
• scopes: attributes, thisTag, caller, variables
• passing data to/from:

Gathering and consuming data

• using custom tags as functional facades
• implicit execution

Leverage Relative Addressing of Template

• use custom tag as a proxy to CFC creation
• CFC names as relative to tag proxy location

Can be recursive!

Examples

regEx Loop  (cf_reLoop) – loop tag to easily access Java’s regular expression matching functionality (faster/more robust than CF)

template mailer (cf_mail) – tag to encapsulate passed in data into a template and then mailed

navigation/navigationItem – set of tags to create a navigation with as many items as needed. handles hover functionality. decouples where a link is going from how it works to get there makes it easier to change either property later.

• cfAssociate is used to pass attributes from parent into the child
• cfExit method=”exittag” is used at the bottom to only let the tag be called once regardless of if it is a self-closed ta

switchLoop – works like cfSwitch but allows for “resetting” of expression. allows for two different cases to be hit.

randomSwitch – works like cfSwitch but a random case is selected.

renderXml – recursive tag to loop through an XML document.

Resources

http://www.bennadel.com/