The type 'undefined' cannot be assigned to type 'CartItem'

While running my program, I encountered the error 'Type 'undefined' is not assignable to type 'CartItem'. Unfortunately, I am unable to resolve this issue :(.

import { Injectable } from '@angular/core';
import { CartItem } from '../common/cart-item';
import { Subject } from 'rxjs';


@Injectable({
  providedIn: 'root',
})
export class CartService {
  cartItems: CartItem[] = [];

  totalPrice: Subject<number> = new Subject<number>();
  totalQuantity: Subject<number> = new Subject<number>();

  constructor() {}

  addToCart(theCartItem: CartItem) {
    // check if we already have the item in our cart
    let alreadyExistsInCart: boolean = false;
    let existingCartItem: CartItem = undefined; // ERROR HERE
  }
}

The error message Type 'undefined' is not assignable to type 'CartItem' is troubling me. How should I go about resolving this issue?

Answer №1

When it comes to the issue at hand

let currentItem: CartItem | null;

this piece of code will set currentItem as null.

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