Here are the ways an HTML element can be accessed in a JavaScript code:
To delete a cookie, we can just set an expiration date and time. Specifying the correct path of the cookie that we want to delete is a good practice since some browsers won’t allow the deletion of cookies unless there is a clear path that tells which cookie to delete from the user’s machine.
function delete_cookie(name) {
document.cookie = name + “=; Path=/; Expires=Thu, 01 Jan 1970 00:00:01 GMT;”;
}
Reading a cookie using JavaScript is also very simple. We can use the document.cookie string that contains the cookies that we just created using that string.
The document.cookie string keeps a list of name-value pairs separated by semicolons, where ‘name’ is the name of the cookie, and ‘value’ is its value. We can also use the split() method to break the cookie value into keys and values.
The simplest way of creating a cookie using JavaScript is as below:
document.cookie = “key1 = value1; key2 = value2; expires = date”;
These are the advantages of JavaScript:
Enhanced Interaction
JavaScript adds interaction to otherwise static web pages and makes them react to users’ inputs.
Quick Feedback
There is no need for a web page to reload when running JavaScript. For example, form input validation.
Rich User Interface
JavaScript helps in making the UI of web applications look and feel much better.
Frameworks
JavaScript has countless frameworks and libraries that are extensively used for developing web applications and games of all kinds.
These are the features of JavaScript:
Properties are the values associated with a JavaScript object.
A JavaScript object is a collection of unordered properties.
Properties can usually be changed, added, and deleted, but some are read only.
JavaScript can “display” data in different ways:
Writing into an HTML element, using innerHTML.
Writing into the HTML output using document.write().
Writing into an alert box, using window.alert().
Writing into the browser console, using console.log().
The let keyword was introduced in ES6 (2015).
Variables defined with let cannot be Redeclared.
Variables defined with let must be Declared before use.
Variables defined with let have Block Scope.
Temporal Dead Zone is a behaviour that occurs with variables declared using let and const keywords.
It is a behaviour where we try to access a variable before it is initialized.
A temporal dead zone (TDZ) is the area of a block where a variable is inaccessible until the moment the computer completely initializes it with a value.