As you have already said, there is no built in functionality on TypeScript as of version 2.8. However, there are ways to get the same result:
Option 1: Using a library
ts-nameof is a library that provides the exact functionality as C# does (no longer recommended). With this you can do:
nameof(console); // => "console"
nameof(console.log); // => "log"
nameof<MyInterface>(); // => "MyInterface"
nameof<MyNamespace.MyInnerInterface>(); // => "MyInnerInterface"
ts-simple-nameof offers an alternative. It basically parses a stringified lambda to figure out the property name:
nameof<Comment>(c => c.user); // => "user"
nameof<Comment>(c => c.user.posts); // => "user.posts"
Option 2: Define a helper function
You can easily define your own nameof that adds the type checking, however it will not refactor automatically as you’ll still need to type a string literal:
const nameof = <T>(name: keyof T) => name;
It will return the passed property name but will generate a compile time error when the property name does not exist on type T. Use it like so:
interface Person {
firstName: string;
lastName: string;
}
const personName1 = nameof<Person>("firstName"); // => "firstName"
const personName2 = nameof<Person>("noName"); // => compile time error
Credits and more information about this
Update on helper function with TypeScript 2.9+
The type keyof T now not only resolves to a string, but to string | number | symbol (ref). If you still want to resolve strings only, use this implementation instead:
const nameof = <T>(name: Extract<keyof T, string>): string => name;