How to check if object has property and property value is true in TypeScript

Question

I want to check if the following object has the property forums and if that property value is true.

{forums: true, pages: true, photos: true, videos: true}

I am using TypeScript Angular 5.

I do this for now and works fine.

let item = 'forums';
if ( this.itemsmodel.hasOwnProperty(item) ) {
   //Which is true. 
   if (this.itemsmodel[item]) {
          item = item;
   } else {
          item = 'pages';
   }
}

Is there an Angular way or TypeScript way for this?

Answer 1

Shortest way ,this will check both by default :

if(this.itemsmodel[item])

First it will try to fetch this.itemsmodel of item if there is not then it will return undefined and if it's found then it will return value,

---

Same but long way of doing :

if(this.itemsmodel[item] && this.itemsmodel[item] === true)

Here first will check if key exists , second will check for the value

---

As result you can convert your code to something like this :

let item = 'forums';
if (this.itemsmodel[item]) {
        item = item;
} else {
        item = 'pages';
}