JavaScript: Create a clock and display the time in each second

Last update on May 30 2022 10:01:54 (UTC/GMT +8 hours)

JavaScript Object: Exercise-8 with Solution

Write a JavaScript program to create a Clock.
Note: The output will come every second.
Expected Console Output:
"14:37:42"
"14:37:43"
"14:37:44"
"14:37:45"
"14:37:46"
"14:37:47"

Sample Solution: -

HTML Code:

<!DOCTYPE html>
  <html>
  <head>
  <meta charset="utf-8">
  <title>Create a clock and display the time in each second </title>
  </head>
  <body>
</body>
  </html>

JavaScript Code:

function my_Clock() 
  {
  this.cur_date = new Date();
  this.hours = this.cur_date.getHours();
  this.minutes = this.cur_date.getMinutes();
  this.seconds = this.cur_date.getSeconds();
  }
my_Clock.prototype.run = function ()
  {
  setInterval(this.update.bind(this), 1000);
  };
my_Clock.prototype.update = function () 
  {
  this.updateTime(1);
  console.log(this.hours + ":" + this.minutes + ":" + this.seconds);
  };
my_Clock.prototype.updateTime = function (secs) 
  {
  this.seconds+= secs;
 if (this.seconds >= 60)
  {
  this.minutes++;
  this.seconds= 0;
  }
 if (this.minutes >= 60)
  {
  this.hours++;
  this.minutes=0;
  }
if (this.hours >= 24)
  {
  this.hours = 0;
  }
};
var clock = new my_Clock();
  clock.run();

Sample Output:

14:45:52
14:45:53
14:45:54
14:45:55
14:45:56
14:45:57
14:45:58
14:45:59
14:46:0
-----

Flowchart:

Live Demo:

See the Pen javascript-object-exercise-8 by w3resource (@w3resource) on CodePen.

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JavaScript: Tips of the Day

How to insert an item into an array at a specific index (JavaScript)?

What you want is the splice function on the native array object.

arr.splice(index, 0, item); will insert item into arr at the specified index (deleting 0 items first, that is, it's just an insert). In this example we will create an array and add an element to it into index 2:

var arr = []; arr[0] = "Jani"; arr[1] = "Hege"; arr[2] = "Stale"; arr[3] = "Kai Jim"; arr[4] = "Borge"; console.log(arr.join()); arr.splice(2, 0, "Lene"); console.log(arr.join());

Ref: https://bit.ly/2BXbp04