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JavaScript

Posted by William Jingga
William Jingga
4,604 Points

'new' Operator in JavaScript. Why we use it? What does it do? and When we use it?

Hi, I am just starting out to learn basic JavaScript. I am doing a challenge on displaying current day dan time. The code looks like this:

var d = new Date();
var weekday = new Array(7);
weekday[0] = "Sunday";
weekday[1] = "Monday";
weekday[2] = "Tuesday";
weekday[3] = "Wednesday";
weekday[4] = "Thursday";
weekday[5] = "Friday";
weekday[6] = "Saturday";

var n = weekday[d.getDay()];
document.getElementById("demo").innerHTML = n;

Though, the program works, i still do not fully understand why using 'new' operator? What does it do and when we use it. Please advise :-)

Thanks,

Will

1 Answer

Steven Pichardo
Steven Pichardo
10,062 Points
Steven Pichardo
Steven Pichardo
10,062 Points

In c# which i am sure is the same case with JavaScript.. the new keyword creates a new instance of the Type of class being called... so new Date() .. is creating a instance of the class Date.