AngualrJS中的Directive制作一个菜单

<ul>
<li data-ng-class="{'active': highlight('/orders')}">
<a href="#/orders">Orders</a>
</li>
</ul> 

vm.highlight = funciton(path){
return $locaiton.path().substr(0, path.lenght) === path;
}

<ul menu-highlighter highlight-class-name="active">
<li><a href="#/customers">Customers</a></li>
<li><a href="#/orders">Customers</a></li>
<li><a href="#/about">Customers</a></li>
</ul> 

(function(){
var injectParams = ['$location'];
var menuHighlighter = function($location){
var link = function(scope, element){
function setActive(){
var path = $location.path();
var className = scope.highlightClassName || 'active';
if(path){
angular.forEac(element.find('li'), function(li){
//<a href="#/customers">Customers</a>
var anchor = li.querySelector('a');
//#/customers
var href=(anchor && anchor.href) ? anchor.href : anchor.getAttribute('data-href').replace('#','');
//customers
var trimmedHref = href.substr(href.indexOf('#/')+1, href.length);
var basePath = path.substr(0, trimmedHref.length);
if(trimmedHref === basePath){
angular.element(li).addClass(className);
} else {
angular.element(li).removeClass(className);
}
});
} 
}
setActive();
scope.$on('$locationChangeSuccess', setActive);
};
return {
restrict: 'A',
scope: {
highlightClassName: '@'
},
link: link
}
};
menuHighlighter.$inject = injectParams;
angular.module('my.directives')
.directive('menuHighlighter', menuHighlighter);
}());