In the given scenario:
class Foo {
constructor(
private one: string,
private two: string,
private three: string) {
}
}
Is there a way to create an array containing the type's properties?
For example, I need to generate an array like:
['One', 'Two', 'Three']
It's important to note that I specifically require the properties to be extracted from the type itself, not from an instance. Otherwise, I could simply use Object.keys(instanceOfFoo).
To retrieve the keys, you can utilize the method Reflect.construct(). Afterwards, you can convert the keys to an array using Object.keys().
Keep in mind: if a key does not have a default value, it will not be generated, as demonstrated with four.
class Foo {
constructor() {
this.one = ''
this.two = ''
this.three = ''
this.four
}
}
console.log(Object.keys(Reflect.construct(Foo, [])))When looking to retrieve the field names from a class, you can achieve this by utilizing the code snippet below:
const fieldNames = Object.keys(myObj) as Array<MyClass>;
I trust this information proves beneficial to you.
After transpilation, the code shown above will result in the following JavaScript code:
var Foo = (function () {
function Foo(one, two, three) {
this.one = one;
this.two = two;
this.three = three;
}
return Foo;
}());
To begin with, I would extract the constructor by using
const c = Foo.prototype.constructorTo start, you must create an instance of const a = new Foo(); and then access it using Object.keys
class Foo {
constructor(
private one: string,
private two: string,
private three: string) {
}
}
const a = new Foo();
console.log(Object.keys(a)); // ["prop"]
UPDATE: It's worth noting that if you aim to retrieve the type, it's not achievable as types are no longer accessible once the code is is compiled.
Examine all the keys within the Foo.prototype object
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