Found 9326 Articles for Object Oriented Programming

In the first example, you are just inheriting amitBaseClass prototype.function SomeClass() { } SomeClass.prototype = Object.create(amitBaseClass.prototype);In the second example, you are executing the constructor function. An instance of amitBaseClass is created and you are inheriting the who complete amitBaseClass object.function SomeClass () { } SomeClass.prototype = new amitBaseClass ();So, both are doing separate work.

To perform unit testing in JavaScript, use Unit.js. It is a cross-platform open-source unit testing framework.ExampleLet’s say the following in your test code −var example = ‘Welcome’; test.string(example) .isEqualTo(‘Welcome’);The function demo() displays a suit of tests, whereas demo1() is an individual test specification,demo('Welcome’, function() {    demo1('Welcome to the website', function() {       var example = ‘Welcome’;       test.string(example)       .isEqualTo(‘Welcome’);    }); });

To disable web browsers’ back button, try to run the following code. This is the code for current HTML page,Example           Disable Browser Back Button                               Next Page               $(document).ready(function() {          function disablePrev() { window.history.forward() }          window.onload = disablePrev();          window.onpageshow = function(evt) { if (evt.persisted) disableBack() }       });     The following is the code for newpage.html,           Go to back page using web browser back button.     a

To get out of the confusion regarding strict comparison, try to run the following code snippet in JavaScript −Exampleswitch(1) {    case '1':       alert('Switch comparison: Not Strict.');       break;    case 1:       alert('Switch comparison: Strict.');       break;    default:       alert(‘Default’); }

In this article, we are going to learn what is JavaScript AES Encryption. AES is an algorithm developed for the encryption of data. AES uses the same key to encrypt and decrypt data, called the symmetric encryption algorithm. AES encryption is Advanced Encryption Standard (AES) to encrypt the data in the application. We use the JavaScript library Forge to perform AES encryption. These algorithms are used in different communication apps such as WhatsApp, Signal, etc. The third-party user cannot be able to decrypt the message, and when the message is reached the destination receiver endpoint, it is decrypted using the ... Read More

We use getIframeContent(frameId), to get the object reference of an iframe in JavaScript. To get the element in an iframe, first we need access the element inside the JavaScript using the document.getElementById() method by passing iframe id as an argument. Using iframetag The tag in HTML specifies an inline frame. This inline frame is used to embed another document within the current HTML document. The element is supported in every browser like (Google Chrome, Microsoft edge/ internet explorer, Firefox, safari, and opera). We are using srcdoc attribute in tag to specify the HTML content of ... Read More

For a negative look-behind in JavaScript, use the following −(^|[^\])"To replace double quotes, you can use the following −str.replace(/(^|[^\])"/g, "$1'")

In this article, we are going to learn how to read data from *.CSV file using JavaScript. To convert or parse CSV data into an array, we need JavaScript’s FileReader class, which contains a method called readAsText() that will read a CSV file content and parse the results as string text. If we have the string, we can create a custom function to turn the string into an array. To read a CSV file, first we need to accept the file. Now let’s see how to accept the csv file from browser using HTML elements. Example Following is the example ... Read More

In this article we are going to learn how to understand JavaScript module pattern. The Module pattern is used to copy the concept of classes, so that we can store both public and private methods and variables inside a single object. Since JavaScript doesn’t support classes, similar to classes that are used in other programming languages like Java or Python. Why use modules? Maintainability − A module is self-contained and aims to lessen the dependencies, so that it can grow and improve independently. Name spacing − In JavaScript, variables outside the scope of a top-level function are global. Because ... Read More

To convert the image into a base64 string using JavaScript, use the FileReader API. You can try to run the following code to get base64string for an image −Example                    function toDataURL(url, callback) {             var httpRequest = new XMLHttpRequest();             httpRequest.onload = function() {                var fileReader = new FileReader();                   fileReader.onloadend = function() {                      callback(fileReader.result);                   }                   fileReader.readAsDataURL(httpRequest.response);             };             httpRequest.open('GET', url);             httpRequest.responseType = 'blob';             httpRequest.send();          }          toDataURL('https://www.tutorialspoint.com/videotutorials/images/tutor_connect_home.jpg', function(dataUrl) {          document.write('Result in string:', dataUrl)       })