Existence and Boolean in javascript

Something Like that:
Existence and Boolean

What is Existence
Goes to internet and looks for a value.

For that you need to create first html code.

HTML

<p>Value of a =  <span id="demo"></span></p>

After that add this JS code.

JS

var a;
a = '';
if(a){
    document.getElementById("demo").innerHTML = 'something is there!';
} else {
    document.getElementById("demo").innerHTML = 'Nothing is there!';
}

You can see a = ”; So now It will be print ‘Nothing is there!’

[codepen_embed height=”265″ theme_id=”0″ slug_hash=”WEoOyX” default_tab=”result” user=”pradeepanvi”]See the Pen Existence and Boolean in javascript by Pradeep Kumar (@pradeepanvi) on CodePen.[/codepen_embed]

Now you can see

Value of a = Nothing is there!

Other side I want this should be print ‘something is there!’

JS

var a;
a = 'something';
if(a){
    document.getElementById("demo").innerHTML = 'something is there!';
} else {
    document.getElementById("demo").innerHTML = 'Nothing is there!';
}

You can see a = ‘something’; So now It will be print ‘something is there!’

[codepen_embed height=”265″ theme_id=”0″ slug_hash=”GvNEXN” default_tab=”result” user=”pradeepanvi”]See the Pen Existence and Boolean in javascript 02 by Pradeep Kumar (@pradeepanvi) on CodePen.[/codepen_embed]

Now you can see

Value of a = something is there!

Let’s try Boolean as well true/false.

JS

var a;
a = false;
if(a){
    document.getElementById("demo").innerHTML = 'something is there!';
} else {
    document.getElementById("demo").innerHTML = 'Nothing is there!';
}

You can see a = false; So now It will be print ‘Nothing is there!’

[codepen_embed height=”265″ theme_id=”0″ slug_hash=”RZogqG” default_tab=”result” user=”pradeepanvi”]See the Pen Existence and Boolean in javascript 03 by Pradeep Kumar (@pradeepanvi) on CodePen.[/codepen_embed]

Now you can see

Value of a = Nothing is there!

JS

var a;
a = true;
if(a){
    document.getElementById("demo").innerHTML = 'something is there!';
} else {
    document.getElementById("demo").innerHTML = 'Nothing is there!';
}

You can see a = ‘something’; So now It will be print ‘something is there!’

[codepen_embed height=”265″ theme_id=”0″ slug_hash=”ZJBywV” default_tab=”result” user=”pradeepanvi”]See the Pen Existence and Boolean in javascript 04 by Pradeep Kumar (@pradeepanvi) on CodePen.[/codepen_embed]

Value of a = something is there!

You can try number as well.