Why use exportAs Property in Angular

Have you used exportAs property of a directive? It could be instrumental in working with public methods of a directive. Let us say; you have created a custom directive to change the background colour of the host element on the mouse hover as below, import { Directive, Input, HostListener, ElementRef } from '@angular/core'; @Directive({ selector: … Continue reading Why use exportAs Property in Angular

Video – Simplifying Dependency Injection and Services in Angular, ng-India Webinar recording

In this webinar, you learn about Tree shakabale service Singleton service Various provideIn options such as forRoot, anyProviders useClass, useFactory, useValue, useExisting Global Error Handling Services in lazy loaded modules https://www.youtube.com/watch?v=OMqqh1eIeXE For more such videos subscribe to the channel here : https://www.youtube.com/c/geek97

When to use viewProviders in Angular – Simplified

I have often seen developers are confused about viewProviders property of the @Componnet decorator.  This post explains to you about the viewProviders option. The viewProviders defines the set of injectable objects that are visible to its view, DOM children. They are not visible to the content children. At the component level, you can provide a service in two ways: Using the providers arrayUsing the viewProviders array. If … Continue reading When to use viewProviders in Angular – Simplified

A JavaScript function inside a Block Scope: Simplified

Scoping determines the visibility of a variable, an object, or a function.  For example, a variable defined inside a function is visible or can be accessed only inside that particular function.   JavaScript has 4 types of scope.  Global scopeFunctional scopeLexical ScopeBlock Scope Out of the above four scoping, Block Scoping became part of JavaScript … Continue reading A JavaScript function inside a Block Scope: Simplified

How to use useClass with Tree Shakable Services in Angular

Recently, I was asked that how can we use providers such as useClass inside a Tree Shakable service?   By default, Angular services are tree shakable, which means if the application does not use them, they are not part of the final bundle. So, if you create a service using CLI as, ng g s Log … Continue reading How to use useClass with Tree Shakable Services in Angular

How to manually pass the value of ‘this’ object in a JavaScript function

Every JavaScript function has a ‘this’ object, and the value of ‘this’ object depends on the way you call the function. To pass the value of ‘this’ manually, you need to call the function indirectly. In JavaScript, you call a function indirectly to pass the value of ‘this’ object manually. Manually calling a function is … Continue reading How to manually pass the value of ‘this’ object in a JavaScript function

Do Angular useExisting providers create a new object of service?

Short answer is NO, the useExisting provider use object created by other tokens. Read on, To learn more about such concepts, join a free webinar on Saturday, 20 June 4 PM IST. RSVP here: https://www.meetup.com/Geek97/events/271292371/ In Angular, providers determine how an object of a particular token gets created. That means whether Angular creates a new … Continue reading Do Angular useExisting providers create a new object of service?

How to make a property non-enumerable in JavaScript?

By default, all the properties of JavaScript objects are enumerable. That means you can enumerate them in a for loop or read them using the Object.values(). Let us consider an object Dog as shown below, let Dog = { name :'foo', age: 9, canRun : true, eatMilk : false } You can enumerate all properties … Continue reading How to make a property non-enumerable in JavaScript?