javascript - angularjs: using $watch in directive to call serivce -

i creating directive 2 day binding input box.

a $watch placed inside link function(which don't know if idea) watch value in input box.

it looks scope.$watch not doing @ all.

i can't figure out problem have tried replace from

scope.$watch('var',srv.dostuff(),true); 

to

scope.$watch('location',srv.dostuff(),true); 

no luck still.

thanks all

http://plnkr.co/edit/4xuqpsclfoojd0bplk14

index.html

<div ng-controller="formctrl"> <form novalidate class="simple-form">     input: <input type="text" ng-model="location" required><br/> </form> <div ng-mydir var="location"></div> <div> 

app.js

var app = angular.module('plunker', []);  app.controller('formctrl', function($scope) {   $scope.location="empty"; });  // service  app.service('srv', function() {   //a function stuff   this.dostuff=function (){      console.log('i done');   }; });   //a diretive calls serivce app.directive('ngmydir', function (srv) {   return {     restrict: 'a',     scope: {         var:'='     },     link: function(scope,elem,attrs,ctrl){     console.log(scope.var);     scope.$watch('var',srv.dostuff(),true);     }   }; }); 

you passed in srv.dostuff(), function call rather function, can use 1 of following solutions:

warp function call srv.dostuff() in function this

link: function (scope, elem, attrs, ctrl) {     scope.$watch('var', function () {         srv.dostuff();     }, true); } 

or simply

link: function (scope, elem, attrs, ctrl) {     scope.$watch('var', srv.dostuff, true); }