CODEWITHSUNDEEP
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GibboK
GibboK

Reputation: 73938

How to use constant in Angular?

I cannot retrieve string from myConstant in a service. What am I doing wrong here and how to fix it? Please provide me sample of code.

   // Define Angular App
    var app = angular.module('App', ['ngRoute', 'LocalStorageModule', 'angular-loading-bar']).constant('myConstant', {
        string: 'myString',
        size: 30
    });


    'use strict';
    app.factory('devicesService', ['$http', 'myConstant', function ($http) {
        var serviceBase = myConstant.string; // PROBLEM HERE
...

Upvotes: 1

Views: 278

Answers (3)

Muhammad Reda
Muhammad Reda

Reputation: 27043

You can add constants to your application using either constant or value.

Both are exactly the same with just a slight difference. That is values inside constant can never be changed, while values inside value can be changed using decorator.

Example:

var app = angular.module('app', []);

app.constant('MY_CONSTANT', {
    value1: 'value 123',
});

app.variable('MY_VARIABLE', {
    value1: 'value 456',
});

app.controller('MainCtrl', function ($scope, MY_CONSTANT, MY_VARIABLE) {
    console.log('constant: ', MY_CONSTANT.value1);
    console.log('variable: ', MY_VARIABLE.value1);
});

Upvotes: 2

gion_13
gion_13

Reputation: 41533

Your code works just fine if you do add the constant as a parameter in yout factory function: 

app.factory('devicesService', ['$http', 'myConstant', function ($http, myConstant) {

In your example, you only added it to the min-safe array, but not in the actual function.
I'm guessing that that's why you had a problem there, because the function wasn't aware of any myConstant variable.

Upvotes: 1

Liad Livnat
Liad Livnat

Reputation: 7475

here is example for using constant in angular: add it to app.js

.constant('AUTH_EVENTS', {
    AuthenticatedSuccess: 'auth-user-success',
})

in you controller:

.controller('ApplicationController', function ($scope, AUTH_EVENTS) {
        console.log(AUTH_EVENTS.AuthenticatedSuccess);
        }

Upvotes: 2

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