javascript image slider i cant find a way to debug sorry for noob question

Question

so I am just starting on my first javascript project. i am trying to make an image slider and its not going well. i wrote this code and although there is no visible bugs i can't get it to work can anyone explane why this code is not working please.

var arr = ["slideshow1.jpg","slideshow2.jpg","slideshow3.jpg"]
var num = 0
function show(){

while (num = arr.length) {
num++
document.getElementById(ssc);
ssc.src = arr[num];
}
}
setInterval(show(),3000);

Answer 1

First off there are some semicolons you need to add.

But the main problem is in your while loop, the condition is
num = arr.length
= is the assignment operator and == should be used for checking if two values are equal.

Also, the while loop would never run because num == arr.length is never met.
You should use another operator, and for what I think you are trying to do, you should use the < operator.

The last problem is with the line:
document.getElementById(ssc)
It should be:
var ssc = document.getElementById("ssc");
This is because the getElementById method returns an element so you have to assign it to a variable.
Also, you needed quotes around the id parameter.

Answer 2

Thx man really halps :)