01. keyof and typeof Operators 관련

• Exercise

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Learn TypeScript > 01. keyof and typeof Operators

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01. keyof and typeof Operators

The keyof type operator works with object types to create a string or numeric literal union of its keys.

The typeof type operator queries the type of a value, allowing you to refer to it in various places.

let person = {name: "Alice", age: 28};
type Person = typeof person;
type PersonKeys = keyof Person;  // "name" | "age"

Exercise

Create a function that updates a property's value in an object, given the object, a property key, and a new value.

Question

function updateProperty<T>(obj: T, key: keyof T, value: any): T {
    // Your code here
    return obj;
}
console.log(updateProperty({name: "Alice", age: 28}, "name", "Bob"));

Answer

function updateProperty<T>(obj: T, key: keyof T, value: any): T {
    // Your code here
    return obj;
}
console.log(updateProperty({name: "Alice", age: 28}, "name", "Bob"));

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