Can I concat a string and a variable to select a DOM element in JavaScript?

Question

I have tried Googling this question but no luck. Probably because I'm asking the wrong way. Any help is much appreciated.

I have variables copy1, copy2, etc. I want to iterate through them and select each one to check if it's contents has a certain number of characters. When I use any variation of the below, it will either console an error or output a string in the console.

var copy1 = document.getElementById('copy1');
var copy2 = document.getElementById('copy2');
var copy3 = document.getElementById('copy3');

for(var i=0;i<4;i++){
 console.log(copy+i);
 console.log("copy"+i);
};

Ideally I would be able to select an element and style that via javascript.

Much appreciated
Thanks All.
Moe

Answer 1

Agree with @jaromanda-x:

var copy1 = document.getElementById('copy1');
var copy2 = document.getElementById('copy2');
var copy3 = document.getElementById('copy3');
for (var i=1; i<4; i++) {
   console.log(window['copy'+i]);
};

Or you can use more simple example, like:

for (var i=1; i<4; i++) {
    var name = 'copy' + i;
    console.log(document.getElementById(name));
};

Or even:

for (var i=1; i<4; i++) {
    console.log(document.getElementById('copy' + i));
};