TYPO3 Core

This is already possible and IMHO it's easier than the proposed solution:

Use this TS-Setup

page.includeCSS {
{$plugin.rzcolorbox.cssPath}
}

the active cssPath

plugin.rzcolorbox.cssPath = colorbox = my/path/to/the.css

plugin.rzcolorbox.cssPath = #

You can even use the constant editor to make it available via check box or selector box.

Not tested though ...

And of course you can deactivate the value depending on another constant the same ways as in the first example.

Setup:

page.includeCSS {
{$plugin.rzcolorbox.deactivate}{$plugin.rzcolorbox.cssPath}
}

Constants for active state:

plugin.rzcolorbox {
  cssPath = colorbox = my/path/to/the.css
  deactivate =
}

Now you can add a single line to the constants to deactivate the whole line on any desired page:

plugin.rzcolorbox.deactivate = #

Can be configured to make use of the constant editor as well.

Hi Jo,

doing this, it is not possible to use the constant editor type=file parameter anymore.
Also a checkbox (type=boolean) for disabling is not possible.

Using a constant inside the if-function should only be an example.
If the objects get a "real" if-function, include stdWrap functionality, this would open up a lot of more possibilities...

Patch set 2 for branch master has been pushed to the review server.
It is available at http://review.typo3.org/8844