Creating a custom interface in TypeScript allows you to define and enforce specific

Looking for guidance on how to properly declare an array of objects using a custom interface in TypeScript. Below is the interface I am working with:

export interface Member {
  name: string,
  isLoggedIn: boolean,
  loginTime: Date
}

I attempted to declare a list of members like so:

public members: Member[] = [
    {name: "John"},
    {name: "Cena"}
];

However, I encountered this error message:

Type '{ name: string; }[]' is not assignable to type 'Member[]'

Any suggestions on the correct way to declare an array of objects with a custom interface to ensure it works correctly and follows best practices?

Answer №1

To handle the situation, you can approach it in two different ways:

export interface User
{
    username: string;
    isLoggedIn?: boolean;
    lastLogin?: Date;
}

let users: User[] = [
    {username: "Alice"},
    {username: "Bob"}
];

Alternatively, consider setting default values during object creation:

export interface User
{
    username: string;
    isLoggedIn: boolean;
    lastLogin: Date;
}

let users: User[] = [
    {username: "Alice", isLoggedIn: false, lastLogin: null},
    {username: "Bob", isLoggedIn: false, lastLogin: null}
];

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