Unable to access array data in Javascript

Question

I am still very new to programming and javascript. The problem I am facing now is I am not able to access the data inside array. Here is my code snippet

global.arr = [];
var id = 12;
for (var i=0; i<5; i++) {
 arr.push(id);
 id++;
}
console.log(arr);
console.log(arr[0]);

this is the console image

My question is that, how can I access into the data and what did i do wrong here?

---

Here is the code I currently have, it still doesn't seem to work:

var arr = [];
var id = 12;
for (var i=0; i<5; i++) {
 arr.push(id);
 id++;
}
console.log(arr);
console.log(arr[0]);

• castletheperson: Is global === window?
• Luke: people stop downvoting questions just because people are new to programming!
• castletheperson: @Luke Please stop assuming the reasons people downvote.
• Marcos Riveros: Not is necessary use "global"
• Asons: @Luke No one is down voting just because people are new to programming, they down vote bad questions, no matter if you have a rep. of 1 or 100000.

Answer 1

Edit: Expanding this a little more:

global is not a JavaScript object. There are global objects , but you access them through window not global. Your code would only work if you had, somewhere else, set global equal to window.

Unless you have a really good reason to use global (or window for that matter), just define the array (and other variables) with var or let.

let arr = [];
let id = 12;
for (let i=0; i<5; i++) {
 arr.push(id);
 id++;
}
console.log(arr);
console.log(arr[0]);

• Emilylaw: Thanks for the explanation. I had changed to declare as var, however I am still getting the same problem, the output is still undefined...
• Luca Kiebel: @Emilylaw In that case, please copy the code you tried just now and add it as an Edit to your question!
• Kurt: @Emilylaw The updated code in your question seems to work just fine now: jsfiddle.net/cngv0fqp

Answer 2

I believe global is the root of your issue. It works when in the browser and using window

window.arr = [];
var id = 12;
for (var i=0; i<5; i++) {
 arr.push(id);
 id++;
}
console.log(arr);
console.log(arr[0]);

However, it is better to not set directly to the window and instead use var arr = [] or let arr = []

• Luke: i would not suggest to use a global variable like "window". as you read, he is new to programming. i think it would be good to improve his thinking
• Kevin Jantzer: I didn't "suggest" anything – just stated "global" is the issue.

Answer 3

To a global array you don't need to set

global.arr = [];

Just set a let variable:

let arr = [];
var id = 12;

See: Let

Then use your code:

let arr = [];
var id = 12;
for (var i=0; i<5; i++) {
 arr.push(id);
 id++;
}
console.log(arr);
console.log(arr[0]);

Answer 4

A variable declared outside a function, becomes GLOBAL. you can declare the variable arr.

var arr = [];
var id = 12;
for (var i=0; i<5; i++) {
 arr.push(id);
 id++;
}
console.log(arr);
console.log(arr[0]);