Make some properties optional in a TypeScript type

Question

If I have a type with all required properties, how can I define another type with the same properties where some of it\'s properties are still required but the rest are opti

Answer 1

You can use combination of Partial and Pick to make all properties partial and then pick only some that are required:

interface SomeType {
    prop1: string;
    prop2: string;
    prop3: string;
    propn: string;
}

type OptionalExceptFor = Partial & Pick

type NewType = OptionalExceptFor

let o : NewType = {
    prop1: "",
    prop2: ""
}