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

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

Hello from typescript undefined

CodePudding user response：

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";

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"

CodePudding user response：

//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
}