Pseudo-classes

Mark Birbeck's picture

Pseudo-classes are classes that are automatically added and removed from controls in a form. For example, if a control is bound to some data that is invalid then the control will have the pseudo-class :invalid, but the moment that the data becomes valid again, the control will have the pseudo-class :valid. This change of state is carried out by the processor, and the author does not need to write any code to take advantage of this.