Calling a variable from a javascript file returns an undefined: Ionic

Question

I'm using the Ionic framework and I want to call a variable from a javascript file, but it returns undefined for the variable and prints the console inside the file.

javascript file:

console.log('Hi!')
var test = "Hello";

typescript file:

import * as testfile from "src/assets/js/customers"

export class CustomersPage implements OnInit {
  test:any='j';
constructor (){
this.test= testfile.test;
console.log('Hello from typescript', this.test);
}

}

The Result

Hi

Hello from typescript undefined

Answer 1

You should export the variable from your JavaScript file for the value to be accessible inside the TypeScript file.

So inside your "src/assets/js/customers" file it should be

export var test = "Hello";

OR

var test = "Hello";
export test;

If this is not a default export you need to import it like

import * as { testfile } from "src/assets/js/customers"

Answer 2

 //Dont forget to export your JS file to use in other files. import * as testfile from "src/assets/js/customers" export class CustomersPage implements OnInit { constructor ( public test: testfile.test ){} async ngOnInit(){ console.log('Hello from typescript', test); } } //or import * as testfile from "src/assets/js/customers" export class CustomersPage implements OnInit { async ngOnInit(){ this.test = testfile.test console.log('Hello from typescript', this.test); } test }