If we have a scenario where:
class ExampleType {
item1?: string,
item2?: string
}
and all the properties are OPTIONAL.
Is there a way to generate an array of property names like:
["item1", "item2"]
I attempted to use
console.log(Object.keys(new ExampleType()))
but it returned an empty array due to the optional properties.
Once TypeScript is transpiled, the compiler will remove any optional properties. Check out TypeScript Playground
TypeScript code:
class MyType {
property1?: string
property2?: string
}
console.log(Object.keys(new MyType()))
Transpiled JavaScript code:
"use strict";
class MyType {
}
console.log(Object.keys(new MyType()));
This explains why you are getting an empty array as output.
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