title: Typescript Array find element by index
body: <p>Finding and assigning a CategoryApi object having categoryId</p>
  
  <pre><code>export class CategoryApi {
      categoryId: number;
      name: string;
  }
  
  categories: CategoryApi[];
  selectedCategory: CategoryApi;
  
  selectedCategory = categories.findByIndex(2); //looking for categoryApi by categoryId = 2
  </code></pre>
  
  <p>I found this javascript option but Typescript is complaining about function</p>
  
  <pre><code>var inventory = [
      {name: 'apples', quantity: 2},
      {name: 'bananas', quantity: 0},
      {name: 'cherries', quantity: 5}
  ];
  
  function findCherries(fruit) { 
      return fruit.name === 'cherries';
  }
  
  console.log(inventory.find(findCherries)); // { name: 'cherries', quantity: 5 }
  </code></pre>