Preguntas y respuestas de entrevista mas solicitadas y pruebas en linea
Plataforma educativa para preparacion de entrevistas, pruebas en linea, tutoriales y practica en vivo

Desarrolla tus habilidades con rutas de aprendizaje enfocadas, examenes de practica y contenido listo para entrevistas.

WithoutBook reune preguntas de entrevista por tema, pruebas practicas en linea, tutoriales y guias comparativas en un espacio de aprendizaje responsivo.

Preparar entrevista
Inicio / Temas de entrevista / JavaScript
Entrevistas simuladas LIVE de WithoutBook JavaScript Temas de entrevista relacionados: 19

Interview Questions and Answers

Conoce las principales preguntas y respuestas de entrevista de JavaScript para principiantes y candidatos con experiencia para prepararte para entrevistas laborales.

Total de preguntas: 59 Interview Questions and Answers

La mejor entrevista simulada en vivo que deberias ver antes de una entrevista

Conoce las principales preguntas y respuestas de entrevista de JavaScript para principiantes y candidatos con experiencia para prepararte para entrevistas laborales.

Interview Questions and Answers

Busca una pregunta para ver la respuesta.

Preguntas y respuestas para nivel intermedio / de 1 a 5 anos de experiencia

Pregunta 2

What is Date class in Javascript? Please explain.

to create a Date object, use new & supply year/month/day/… as desired

today = new Date(); // sets to current date & time

newYear = new Date(2002,0,1); //sets to Jan 1, 2002 12:00AM

methods include:

newYear.getYear() can access individual components of a date
newYear.getMonth()
newYear.getDay()
newYear.getHours()
newYear.getMinutes()
newYear.getSeconds()
newYear.getMilliseconds()
Guardar para repaso

Guardar para repaso

Guarda este elemento en marcadores, marcalo como dificil o agregalo a un conjunto de repaso.

Abrir mi biblioteca de aprendizaje
Es util?
Agregar comentario Ver comentarios
Pregunta 3

What are Math routines in Javascript?

the Math object contains functions and constants

Math.sqrt
Math.pow
Math.abs
Math.max
Math.min
Math.floor
Math.ceil
Math.round

Math.PI
Math.E

Math.random function returns number in [0..1)
Guardar para repaso

Guardar para repaso

Guarda este elemento en marcadores, marcalo como dificil o agregalo a un conjunto de repaso.

Abrir mi biblioteca de aprendizaje
Es util?
Agregar comentario Ver comentarios
Pregunta 4

What about Navigator object?

navigator.appName property that gives the browser name.
navigator.appVersion property that gives the browser version.
navigator.userAgent property that gives the browser related information.
Guardar para repaso

Guardar para repaso

Guarda este elemento en marcadores, marcalo como dificil o agregalo a un conjunto de repaso.

Abrir mi biblioteca de aprendizaje
Es util?
Agregar comentario Ver comentarios
Pregunta 5

Explain String functions in Javascript.

a class defines a new type (formally, Abstract Data Type)
encapsulates data (properties) and operations on that data (methods)

a String encapsulates a sequence of characters, enclosed in quotes

properties include
length : stores the number of characters in the string

methods include
charAt(index) : returns the character stored at the given index
(as in C++/Java, indices start at 0)
substring(start, end) : returns the part of the string between the start
(inclusive) and end (exclusive) indices
toUpperCase() : returns copy of string with letters uppercase
toLowerCase() : returns copy of string with letters lowercase


to create a string, assign using new or just make a direct assignment (new is implicit)

word = new String("foo"); word = "foo";

properties/methods are called exactly as in C++/Java

word.length word.charAt(0)
Guardar para repaso

Guardar para repaso

Guarda este elemento en marcadores, marcalo como dificil o agregalo a un conjunto de repaso.

Abrir mi biblioteca de aprendizaje
Es util?
Agregar comentario Ver comentarios
Pregunta 6

How do we get JavaScript onto a web page?

You can use several different methods of placing Javascript in you pages.
You can directly add a script element inside the body of page.
1. For example, to add the "last updated line" to your pages, In your page text, add the following:
<p>blah, blah, blah, blah, blah.</p>
<script type="text/javascript" >
<!-- Hiding from old browsers
document.write("Last Updated:" +
document.lastModified);
document.close();
// -->
</script>
<p>yada, yada, yada.</p>

(Note: the first comment, "<--" hides the content of the script from browsers that don't understand javascript. The "// -->" finishes the comment. The "//" tells javascript that this is a comment so javascript doesn't try to interpret the "-->". If your audience has much older browsers, you should put this comments inside your javascript. If most of your audience has newer browsers, the comments can be omitted. For brevity, in most examples here the comments are not shown. )
The above code will look like this on Javascript enabled browsers,
2. Javascript can be placed inside the element
Functions and global variables typically reside inside the <head> element.
<head>
<title>Default Test Page</title>
<script language="JavaScript" type="text/javascript">
var myVar = "";
function timer(){setTimeout('restart()',10);}
document.onload=timer();
</script>
</head>

Javascript can be referenced from a separate file
Javascript may also a placed in a separate file on the server and referenced from an HTML page. (Don't use the shorthand ending <script ... />). These are typically placed in the <head> element.
<script type="text/javascript" SRC="myStuff.js"></script>
Guardar para repaso

Guardar para repaso

Guarda este elemento en marcadores, marcalo como dificil o agregalo a un conjunto de repaso.

Abrir mi biblioteca de aprendizaje
Es util?
Agregar comentario Ver comentarios
Pregunta 7

How can JavaScript make a Web site easier to use? That is, are there certain JavaScript techniques that make it easier for people to use a Web site?

JavaScript's greatest potential gift to a Web site is that scripts can make the page more immediately interactive, that is, interactive without having to submit every little thing to the server for a server program to re-render the page and send it back to the client. For example, consider a top-level navigation panel that has, say, six primary image map links into subsections of the Web site. With only a little bit of scripting, each map area can be instructed to pop up a more detailed list of links to the contents within a subsection whenever the user rolls the cursor atop a map area. With the help of that popup list of links, the user with a scriptable browser can bypass one intermediate menu page. The user without a scriptable browser (or who has disabled JavaScript) will have to drill down through a more traditional and time-consuming path to the desired content.
Guardar para repaso

Guardar para repaso

Guarda este elemento en marcadores, marcalo como dificil o agregalo a un conjunto de repaso.

Abrir mi biblioteca de aprendizaje
Es util?
Agregar comentario Ver comentarios
Pregunta 8

How to create arrays in JavaScript?

We can declare an array like this
var scripts = new Array();
We can add elements to this array like this

scripts[0] = "PHP";
scripts[1] = "ASP";
scripts[2] = "JavaScript";
scripts[3] = "HTML";

Now our array scrips has 4 elements inside it and we can print or access them by using their index number. Note that index number starts from 0. To get the third element of the array we have to use the index number 2 . Here is the way to get the third element of an array.
document.write(scripts[2]);
We also can create an array like this
var no_array = new Array(21, 22, 23, 24, 25);
Guardar para repaso

Guardar para repaso

Guarda este elemento en marcadores, marcalo como dificil o agregalo a un conjunto de repaso.

Abrir mi biblioteca de aprendizaje
Es util?
Agregar comentario Ver comentarios
Pregunta 10

How to write a script for "Select" lists using javascript?

1. To remove an item from a list set it to null
mySelectObject.options[3] = null;
2. To truncate a list set its length to the maximum size you desire
mySelectObject.length = 2;
3. To delete all options in a select object set the length to 0.
mySelectObject.length
Guardar para repaso

Guardar para repaso

Guarda este elemento en marcadores, marcalo como dificil o agregalo a un conjunto de repaso.

Abrir mi biblioteca de aprendizaje
Es util?
Agregar comentario Ver comentarios
Pregunta 11

Is a Javascript script faster than an ASP script?

Yes.Since Javascript is a client-side script it does require the web server's help for its
computation,so it is always faster than any server-side script like ASP,PHP,etc..
Guardar para repaso

Guardar para repaso

Guarda este elemento en marcadores, marcalo como dificil o agregalo a un conjunto de repaso.

Abrir mi biblioteca de aprendizaje
Es util?
Agregar comentario Ver comentarios

Lo mas util segun los usuarios:

Copyright © 2026, WithoutBook.