The "ifnot" binding

Purpose

The ifnot binding is exactly the same as the if binding, except that it inverts the result of whatever expression you pass to it. For more details, see documentation for the if binding.

Note: “ifnot” is the same as a negated “if”

The following markup:

<div data-bind="ifnot: someProperty">...</div>

… is equivalent to the following:

<div data-bind="if: !someProperty()">...</div>

… assuming that someProperty is observable and hence you need to invoke it as a function to obtain the current value.

The only reason to use ifnot instead of a negated if is just as a matter of taste: many developers feel that it looks tidier.