How to equals correctly a Variable with String in Angular.js

Question

I will use the Data from GET Request in Angular.js, like below.

    var app = angular.module('Saidas',[]);
    app.controller('Status', function($scope, $http, $interval) {
        $interval(function(){
            var request = $http.get('/SaidasSite');    
            request.success(function(data) {
                if (data='QTD1LEDON') {
                    $('#QTD1LAMP').bootstrapToggle('on');
                } else (data='QTDLEDOFF'){
                    $('#QTD1LAMP').bootstrapToggle('off');
                } else (data='QTD2LEDON'){
                    $('#QTD2LAMP').bootstrapToggle('on')
                } else { $('#QTD1LAMP').bootstrapToggle('on'); }
            })
            .error(function(data){
                console.log('Error: ' + data);
            });
        }, 5000);

When i receive "QTD1LEDON", i will toogle a Button in my Code to "ON", when i receive QT1LEDOFF, i will toogle to "OFF". But when i do this code, the comparison always a "QTD1LEDON". What am I doing wrong?

Sorry for my bad english

Did you check what the 'data' parameter in success callback is returning? — Gangadhar Jannu, Oct 04 '16 at 15:00
Check the data like Jannu said. console.log(data) why don't you use an ng-model instead? Replace the first 2 else by else if. — Wandrille, Oct 04 '16 at 15:01
you are comparing right ? So why the single `=` (this is assignment operator). For comparing use `==`(comparison operator). Try & let me know — Nikhil Nanjappa, Oct 04 '16 at 15:04
http://stackoverflow.com/questions/359494/which-equals-operator-vs-should-be-used-in-javascript-comparisons — NicolasMoise, Oct 04 '16 at 15:07

score 1 · Accepted Answer · answered Oct 04 '16 at 15:05

1

You are making an assigment instead a comparison. So, in the first if you are giving to data the value 'QTD1LEDON', and always is true.

You need to fix:

if (data='QTD1LEDON') {

with:

if (data==='QTD1LEDON') {

answered Oct 04 '16 at 15:05

Ramon-san

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score 0 · Answer 2 · answered Oct 04 '16 at 15:05

0

You should use === for comparison, not = which is for assignment.

answered Oct 04 '16 at 15:05

NicolasMoise

7,261
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iamalismith · Answer 3 · 2016-10-04T15:16:12.713

0

In javascript you make a comparison using === or ==.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Comparison_Operators

In your code you use =, which simply assigns a value to your data variable, meaning the condition always evaluates as truthy: if (data='QTD1LEDON') {

You need to use == or === and it will behave as you are expecting:

if (data === 'QTD1LEDON') {

edited Oct 04 '16 at 15:16

answered Oct 04 '16 at 15:06

iamalismith

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9
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score 0 · Answer 4 · answered Oct 04 '16 at 15:31

You are making assignments instead of comparisons and you also have 3 else statements where you should only have 1, so you should have something like

if (data === 'QTD1LEDON') {
     ...
} else if (data === 'QTDLEDOFF') {
     ...
} else if (data === 'QTD2LEDON') {
     ...
} else { ... }

How to equals correctly a Variable with String in Angular.js

4 Answers4