If one is to use all four function, the directive will follow this form:
myApp.directive( 'myDirective', function () {
return {
restrict: 'EA',
controller: function( $scope, $element, $attrs, $transclude ) {
// Controller code goes here.
},
compile: function compile( tElement, tAttributes, transcludeFn ) {
// Compile code goes here.
return {
pre: function preLink( scope, element, attributes, controller, transcludeFn ) {
// Pre-link code goes here
},
post: function postLink( scope, element, attributes, controller, transcludeFn ) {
// Post-link code goes here
}
};
}
};
});
Notice that compile returns an object containing both the pre-link and post-link functions; in Angular lingo we say the compile function returns a template function.
If pre-link
isn't necessary, the compile function can simply return the post-link function instead of a definition object, like so:
myApp.directive( 'myDirective', function () {
return {
restrict: 'EA',
controller: function( $scope, $element, $attrs, $transclude ) {
// Controller code goes here.
},
compile: function compile( tElement, tAttributes, transcludeFn ) {
// Compile code goes here.
return function postLink( scope, element, attributes, controller, transcludeFn ) {
// Post-link code goes here
};
}
};
});
Sometimes, one wishes to add a compile
method, after the (post) link
method was defined. For this, one can use:
myApp.directive( 'myDirective', function () {
return {
restrict: 'EA',
controller: function( $scope, $element, $attrs, $transclude ) {
// Controller code goes here.
},
compile: function compile( tElement, tAttributes, transcludeFn ) {
// Compile code goes here.
return this.link;
},
link: function( scope, element, attributes, controller, transcludeFn ) {
// Post-link code goes here
}
};
});
If no compile function is needed, one can skip its declaration altogether and provide the post-link function under the link
property of the directive's configuration object:
myApp.directive( 'myDirective', function () {
return {
restrict: 'EA',
controller: function( $scope, $element, $attrs, $transclude ) {
// Controller code goes here.
},
link: function postLink( scope, element, attributes, controller, transcludeFn ) {
// Post-link code goes here
},
};
});
In any of the examples above, one can simply remove the controller
function if not needed. So for instance, if only post-link
function is needed, one can use:
myApp.directive( 'myDirective', function () {
return {
restrict: 'EA',
link: function postLink( scope, element, attributes, controller, transcludeFn ) {
// Post-link code goes here
},
};
});