Important Front End Developer (AngularJS) Interview Preparation Guide

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For variables in JavaScript, you have to add semi-colon at the end of it to execute while in CoffeeScript there is no need to add Semi-colon at the end of the statement. Unlike, JavaScript, CoffeeScript adds up semi-colon with ease.

Native – existing in JavaScript. Host – existing in the environment.

The basic rule for Coffee Script

☛ Whitespace matters: There are no curly braces in CoffeeScript
☛ No parentheses: Functions that take arguments do not require parentheses

Yes, Angular can use jQuery if it's present in your app when the application is being bootstrapped. If jQuery is not present in your script path, Angular falls back to its own implementation of the subset of jQuery that we call jQLite.

Due to a change to use on()/off() rather than bind()/unbind(), Angular 1.2 only operates with jQuery 1.7.1 or above.

See section on using prototypes to call functions on common data types in JavaScript Objects & Prototypes.

A stylesheet is template file consisting of font and layout settings to give a standardized look to a website or web application. To keep a consistent look and feel to a project, there should only be one stylesheet. I like to ask this question to judge problem-solving, communication and team skills.

In a nutshell, responsive is fluid and flexible, whereas adaptive adapts to the detected device/screen size.

== compares the value; === compares the value and the type:


"5" == 5; // true

"5" === 5; // false

Using the ng-show and ng-disabled directives.

<div class="dataControlPanel"
ng-show="accounts.releasePortfolios">

<div class="dataControlButtons">
<button class="btn btn-primary btn-small"
ng-click="saveComments()" ng-disabled="disableSaveButton">Save</button>
<button class="btn btn-primary btn-small"
ng-click="releaseRun()" ng-disabled="disableReleaseButton">Release</button>
</div>
</div>

The workflow of a modern front end developer has changed vastly in the past four or five years. A huge array of tools are available to build organised, scalable web applications, which reduce complex and automate repetitive tasks. Each developer will share a different unique workflow which will give you valuable insight into their organisational patterns and general technical preferences.

Prototype-based inheritance allows you to create new objects with a single operator; class-based inheritance allows you to create new objects through instantiation. Prototypes are more concrete than classes, as they are examples of objects rather than descriptions of format and instantiation.

Prototypes are important in JavaScript because JavaScript does not have classical inheritance based on classes; all inheritances happen through prototypes. If the JavaScript runtime can’t find an object’s property, it looks to the object’s prototype, and continues up the prototype chain until the property is found.

When you want an element on the left or right of the floating element not to wrap around it, you can use clear.

Each Angular application has exactly one root scope, but may have several child scopes. The application can have multiple scopes, because child controllers and some directives create new child scopes. When new scopes are created, they are added as children of their parent scope. This creates a hierarchical structure similar to the DOM where they're attached.

When Angular evaluates a bound variable like say {{firstName}}, it first looks at the scope associated with the given element for the firstName property. If no such property is found, it searches the parent scope and so on until the root scope is reached. In JavaScript this behaviour is known as prototypical inheritance, and child scopes prototypically inherit from their parents. The reverse is not true. i.e. the parent can't see it's children's bound properties.

At the highest level, Angular does look like a just another templating system. But there is one important reason why the Angular templating system is different, that makes it very good fit for application development: bidirectional data binding. The template is compiled in the browser and the compilation step produces a live view. This means you, the developers, don't need to write code to constantly sync the view with the model and the model with the view as in other templating systems.

Float is used when you want to make an element of your page (usually an image) be pushed to the right or left and make other elements wrap around it.

A GET request is typically used for things like AJAX calls to an API (insignificant changes), whereas a POST request is typically used to store data in a database or submit data via a form (significant changes). GET requests are less secure and can be seen by the user in the URL, whereas POST requests are processed in two steps and are not seen by the user. Therefore, POST requests are more secure.

IIFE stands for immediately-invoked function expression; it executes immediately after created by adding a () after the function.

Use the ng-init directive.

<div ng-controller="apps/dashboard/account" ng-switch
on="!!accounts" ng-init="loadData()">

This can be tricky and the best way to keep in your head is to memorise because if you try to relate javascript null to other languages, it will get more confusing.
In javascript, null is an object with no value and undefined is a type.

typeof null; // "object"
typeof undefined; // "undefined"
var a;
var b = null;
a == b; // "true" because their values are the same
a === b; // "false". they have different types

A style sheet is a template file consisting of font and layout settings to give a standardized look to a website or web application. To keep a consistent look and feel to a project, there should only be one style sheet. I like to ask this question to judge problem-solving, communication, and team skills.

The MVC typically helps you to organize web application into a well-structured pattern. This makes it a lot easier to maintain code and is well-known by developers.

Popular MVCs are as follows:

☛ AngularJS
☛ Backbone.js

For this question, what you’re really trying to find out has nothing to do with whether they have used an MVC, but rather their preference and level of experience with it. If the candidate is able to articulate why they prefer one over the other, you’ll know that they’re engaged in what they do and care about the tools that they use.

Why is this important?
It’s important as you have to be able to trust your front-end developer to keep up to date with new and relevant technologies. They should also have a clear idea about what should be used and when it should be used.

Event delegation allows you to avoid adding event listeners for specific nodes. Instead, you can add a single event listener to a parent element.

Three.js is an open source JavaScript 3D library that enables you to make and display animated, interactive 3D computer graphics on any compatible web browser without having a dependency on proprietary plug-ins.

Key features of Three.js include

☛ Renderers
☛ Scenes
☛ Cameras
☛ Lights
☛ Animations
☛ Materials
☛ Shaders
☛ Objects
☛ Geometry
☛ Loaders
☛ Export/Import
☛ Debugging
☛ Support

Flask uses thread local objects internally so that user don’t have to pass objects around from function to function within a request in order to stay threadsafe. This approach is useful, but it requires a valid request context for dependency injection or when attempting to reuse code which uses a value pegged to the request.

Mode-View-Controller (MVC) is a design pattern. It can be represented in AngularJS framework as follow:

Model: Model in AngularJS is just a JavaScript object which contains properties either primitive such as string, integer, Boolean, array or complex type object. Its main responsibility to hold data that come from controller or service. Some time it also contains business logic which related to view.

View: It’s just a plain HTML page with embedded AngularJS directives and expression. In AngularJS we mainly represent model data through view.

Controller: It’s a JavaScript function which main responsibility to bind model data to view and vise-versa. It can also contains business logic through which it determine which model goes to which view. Controller also responsible for bind model data that come http request or other services.