Guide to starting a typed array in Typescript

I have an array called "cart" of objects that is initially empty, but structured like this:

cart:[{name:any, rate:number, qty:number, discount:number, subtotal:number}]

When I attempt to add data to it like so:

cart:[{name:any, rate:number, qty:number, discount:number, subtotal:number}];

and then try to get the length using:

Object.keys(this.cart).length

I encounter an error that says:

`TypeError: Cannot convert undefined or null to object`

Additionally, I am seeking ways to clear all elements in an Array.

angulartypescript

Answer №1

From what I know, the solution below should meet your needs:

interface IItem {
    itemName: any;
    itemRate: number;
    itemQuantity: number;
    itemDiscount: number;
    itemSubtotal: number
}
let shoppingCart: Array<IItem> = [];

Answer №2

To start, make sure to set up the array:

items = [];

Next, use this code snippet to remove all items from the array.

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