ill keep this simple, because other examples have been complicated and I havent been able to follow.

i have an array

var bigArray = ["cat", "dog","mouse"];

I would like to take this and create new (3) arrays based on the objects in the array

var cat =[];
var dog =[];
var mouse =[];

seemingly, this does not work.

bigArray.forEach(let array[element] = new Array(array[element]));
console.log(arraycat);

CodePudding user response：

You can't really create variables dynamically, except if you make them global by binding them to the window object, which is not a good idea.

A common way of doing this is to create an empty object, then store whatever you want inside by adding key/value pairs to it.

const bigArray = ["cat", "dog","mouse"];

let animals = {};

bigArray.forEach( species => animals[species] = [ 1, 2 ,3, 4 ] ); 

console.log("cat = ", animals.cat)
console.log("dog = ", animals.dog)

<iframe name="sif1" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

CodePudding user response：

var bigArray = ["cat", "dog","mouse"];

bigArray.forEach(function(item) {
 window[item] = []; 
});
console.log(window.cat);
console.log(window.dog);
console.log(window.mouse);
// or
console.log(cat);
console.log(dog);
console.log(mouse);

<iframe name="sif2" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

CodePudding user response：

If you are using web browsers, you can bind them to window.

Provided this wont work with nodejs or javascript framework working for non web browsers.

var bigArray = ["cat", "dog","mouse"];
bigArray.forEach(node => {
  window[node] = [];
});
console.log(cat, dog, mouse);

<iframe name="sif3" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

The above solution is considered as a bad practice. If you just want to have nodes with same name as in array, you can create this node inside an object just like below.

const bigArray = ["cat", "dog","mouse"];
const myObj = {};
bigArray.forEach(node => {
  myObj[node] = [];
});
console.log(myObj.cat, myObj.dog, myObj.mouse);

<iframe name="sif4" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

If you need to create distict variables, you can use the first approach.

If you are ok to use the same nodes from an object, you can use the second approach.