How to use the charCodeAt method in JavaScript

by Janeth Kent Date: 22-07-2021 javascript


The charCodeAt method is accepted by strings in JavaScript, returning the 16-bit Unicode code of the character at the position we pass as a parameter to the method.

The charCodeAt method can be used with both standard strings defined with single or double quotes and String objects or literal templates.

In this example we get the Unicode codes of the characters in position 1 of the string 'JavaScript':

 
const codetest = 'JavaScript'.charCodeAt(0) // 74  
const codetest = 'JavaScript'.charCodeAt(1) // 97
 

If there is no character in the position we pass as parameter to the method, the returned value will be NaN. This case will occur when we want to obtain the code of the character that is in a position whose value is equal to or greater than the length of the string. The NaN value means Not a Number, returned when the result obtained is not a numeric value.

In this example we get the Unicode code of the character at position 20 of the string 'JavaScript':

In the following example we get the Unicode code of the character at position 20 of the string 'JavaScript':

 
const codetest = 'JavaScript'.charCodeAt(20) // NaN
 

The charCodeAt method works in exactly the same way with String objects, as you can see in the following example

 
const chain = new String('JavaScript');  const codetest = chain.charCodeAt(1); // 97
 

The charCodeAt method, like all methods commonly used with strings in JavaScript, is case sensitive. Therefore, the character A is considered different from the character a.

In addition, you can use the toString method with the result obtained by the charCodeAt method to convert the Unicode code into a character.

In case you want to get the representation of special characters whose representation consists of two 16-bit units, you have to use the charCodeAt method twice, with two consecutive indices. Alternatively, you can also use the codePointAt method. Alternatively, you can also use the codePointAt method. For more information about this method, see how to use the codePointAt method in JavaScript.

 

Read also:

How to use the charAt method in JavaScript

Strings in JavaScript: What they are and how to use them

 
by Janeth Kent Date: 22-07-2021 javascript hits : 97  
 
Janeth Kent

Janeth Kent

Licenciada en Bellas Artes y programadora por pasión. Cuando tengo un rato retoco fotos, edito vídeos y diseño cosas. El resto del tiempo escribo en MA-NO WEB DESIGN END DEVELOPMENT.

 
 
 

Related Posts

How to use the codePointAt method in JavaScript

The JavaScript codePointAt method has more or less the same function as the charCodeAt method, used to get the 16-bit Unicode representation of the character at a certain position in…

How to check if a value is a number in JavaScript

In this short tutorial we are going to look at the various methods that exist to find out if a value is a number in JavaScript.   1. Using the isNaN() function   One…

How to use the charAt method in JavaScript

The charAt method is accepted by strings in JavaScript, returning the position of the character passed as a parameter within the string. If the string contains multiple occurrences of the character…

Strings in JavaScript: What they are and how to use them

In this tutorial we are going to explain what strings are and how they are used in JavaScript. The tutorial is intended for people who are learning to program in…

Dates in local format with Javascript

In the articles we have about dates in JavaScript we were missing one about how to create dates in local format with JavaScript. That is to say, being able to…

Formatting hours in Javascript

Continuing with the set of articles that talk about internationalisation elements, like the previous one where we talked about relative dates in JavaScript, we will see in this one how…

Request data with prompt in JavaScript

After having published several articles about how to manipulate arrays and dates, today I will publish a post that some of you will find too basic and others will find…

Relative dates in JavaScript

One of the interesting things about the internationalisation library represented in the Int object is the handling of relative dates in Javascript. This handling allows us to represent a date…

How to access webcam and grab an image using HTML5 and Javascript

We often use webcams to broadcast video in real time via our computer. This broadcast can be viewed, saved and even shared via the Internet. As a rule, we need…

The JavaScript forEach loop

We have already talked about how to handle some of loops  types in Javascript including for, for-in and for-off loops. In the case of today we are going to see how…

What are React Hooks and what problems they solve

Working with React, - and before the release of Hooks in version 16.8 -  there was always the possibility to create components in three different ways based on a number of…

Flattening arrays in JavaScript

When we are handling arrays that are arrays or have multiple dimensions it can be very useful to know how to flatten arrays in JavaScript. That is to say, to…

We use our own and third-party cookies to improve our services, compile statistical information and analyze your browsing habits. This allows us to personalize the content we offer and to show you advertisements related to your preferences. By clicking "Accept all" you agree to the storage of cookies on your device to improve website navigation, analyse traffic and assist our marketing activities. You can also select "System Cookies Only" to accept only the cookies required for the website to function, or you can select the cookies you wish to activate by clicking on "settings".

Accept All Only sistem cookies Configuration