Ways to display all properties of a component

I am seeking a way to retrieve all the component properties, including private and public ones, in Angular.

My attempts so far include:

ngOnInit() {
    console.log(this.constructor.prototype);
}

However, this code only displays properties with defined getter methods. It does not show properties without getters or setters. Additionally, it also lists component methods, which I am not interested in.

Interestingly, it does not even show public properties (those without getters).

I have also tried:

console.log(this.constructor.prototype.hasOwnProperty('_queryState'));

But it simply returns false, indicating that it did not recognize the property.

This question on Stack Overflow did not provide a solution either.

So, my main question remains: How can I effectively list all properties?

In case anyone wonders why I need this information, it is for the purpose of unit testing.

Answer №1

If you want to access object properties in JavaScript, you can make use of the Object.keys method:

let person = {name: 'Alice', age: 30, city: 'New York'};
let keys = Object.keys(person);

for(let key of keys) {
  console.log('person[' + key + '] = ' + person[key]);
}

Check out this example on StackBlitz.

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