How to change css properties with javascript

Question

var lights = ("blue", "white", "violet");

function check() {

for(var i = 0; i <= lights.length; i++) {
    if(i = "blue") {

  } else if (i = "white") {

  } else if (i = "violet") {

  }
}

I need help, I want to be able to change a css property which is not listed here but it consists of background colour is blue and I want to change it to another colour while accessing javascript. If anyone knows, please can they tell me step by step what to do please, thank you

1) Google [set CSS with JavaScript](https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=set%20css%20with%20javascript) 2) You're welcome. — hungerstar, Nov 08 '16 at 22:27
What are you trying to do? You need to post a more detailed question. — Jacob G, Nov 08 '16 at 22:27
Bonus tip #2 @dan08 your comparison is wrong, use `===` instead of `==` — Valentin Roudge, Nov 08 '16 at 22:28
That whole code makes no sense, you mean. That array notation. — Valentin Roudge, Nov 08 '16 at 22:30
Bonus tip #4 `lights[i]` instead of `i` in the comparisons, thanks @JacobGray — Valentin Roudge, Nov 08 '16 at 22:30
You will need to be more detailed when asking questions in order to get a helpful answer. For instance, you've not included the css that you want to change, nor any html markup. Please revise your question accordingly. — B2K, Nov 08 '16 at 22:37

score 3 · Answer 1 · answered Nov 08 '16 at 22:27

3

If you want to use pure Javascript you can use something like this to set a background color for an element:

document.getElementById("myDiv").style.backgroundColor = "blue";

answered Nov 08 '16 at 22:27

Aram

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score 1 · Answer 2 · answered Nov 08 '16 at 22:30

There are a couple of ways to change a CSS property of an element. Both methods require accessing HTML DOM elements by ID or class.

Classic Javascript:

document.getElementById('someID').style.backgroundColor = "blue";

jQuery:

$('#someID').css('backgroundColor', 'blue');

How to change css properties with javascript

2 Answers2