MANOJ G Found it. It's working !! Can you also check it once

class TestFilter {
    constructor($http, TestService) {
        this.$http = $http;
        this.TestService = TestService;
        return (input, param1) => {
            console.log($http);
            console.log(this.TestService.testFn());
            console.log('Filter Param: ', param1);
            return input.slice(1);
        }
    }
    static filter($http, TestService){ 
        TestFilter.instance = new TestFilter($http, TestService);
        return TestFilter.instance;
    }
}
TestFilter.filter.$inject = ['$http', 'TestService'];
export default angular.module('yourApp').filter('letterSlice', TestFilter.filter);

MANOJ G Thank you. I have tried your approach and it'sh working for a basic scenario where thereis no dependencies required for your filter. If there are dependencies it fails. I guess it must require something similar to directive.

class TestFilter {
     constructor(TestService) {
        return (input, param1) => {
            console.log('Filter Param: ', param1);
            return input.slice(1);
        }
    }
}
TestFilter.$inject = ['TestService'];
export default angular.module('yourApp').filter('letterSlice', () => new TestFilter());

MANOJ G I'm using something like below for Directive and it seems like working, But not able to find a proper example for Filters

import template from './test.directive.html';

class ExampleDirective {
 constructor($http) {
    this.templateUrl = template; // Template or template Url
    this.restrict = 'E'; // Element, Attribute, Class or Comment
    this.scope = { // Bindings required
 oneWay: '@',
 twoWay: '=',
 testFn: '&'
    };
    this.controllerAs = 'eCtrl';
    this.bindToController = true; //This will bind data to controller's this but not to scope. So it's good to use it.
    this.controller = ExampleController; //Controller Initialization
    this.$http = $http; // Dependencies for Directive, if any required
  }
 link(scope, ele, attrs) { // Link function
 console.log('LINK FUNCTION:', scope, ele, attrs);
  }
  static directiveFactory($http){ // This is what is exposed for directive
 ExampleDirective.instance = new ExampleDirective($http);
    return ExampleDirective.instance;
  }
}

ExampleDirective.directiveFactory.$inject =  ['$http']; // Inject Dependencies for Directive

class ExampleController {
 constructor($scope, $http) {
 console.log('DIRECTIVE CONTROLLER');
    this.$scope = $scope;
    this.$http = $http;
  }
}

ExampleController.$inject = ['$scope', '$http']; // Inject Dependencies for Controller


export default angular.module('yourApp').directive('testDir', ExampleDirective.directiveFactory);

I have written a blog on a directive named "setHeight.ts" with class attribute using ES6 class.

Here I have used typescript.Please let me know if you have any more doubts.Writing filters is also the same approach like directive

mytechnofan.blogspot.in/2017/03/that-uses-attribu…