I am creating an array of objects in TypeScript:
userTestStatus xxxx = {
"0": { "id": 0, "name": "Available" },
"1": { "id": 1, "name": "Ready" },
"2": { "id": 2, "name": "Started" }
};
Can someone tell me how I could declare its type correctly? Is it possible to do inline or would I need two definitions?
I'm looking to replace the xxx
with a type declaration, so that later on TypeScript would alert me if I used something like userTestStatus[3].nammme
by mistake.
You are better off using a native array instead of an object literal with number-like properties, so that numbering (as well as numerous other array functions) are taken care of off-the-shelf.
What you are looking for here is an inline interface definition for your array that defines every element in that array, whether initially present or introduced later:
let userTestStatus: { id: number, name: string }[] = [
{ "id": 0, "name": "Available" },
{ "id": 1, "name": "Ready" },
{ "id": 2, "name": "Started" }
];
userTestStatus[34978].nammme; // Error: Property 'nammme' does not exist on type [...]
If you are initializing your array with values right away, the explicit type definition is not a necessity; TypeScript can automatically infer most element types from the initial assignment:
let userTestStatus = [
{ "id": 0, "name": "Available" },
...
];
userTestStatus[34978].nammme; // Error: Property 'nammme' does not exist on type [...]