JAVASCRIPT

JAVASCRIPT BOOLEAN OPERATORS

Javascript boolean operators, also known as logical operators allow you to evaluate multiple expressions at a time. Returns either true or false.

These three boolean operators are &&, || and ! and are explained below with examples:

And Operator: &&

Check if both are conditions are satisfied.

Example:

if(firstName=='John' && lastName=='Smith')
{
alert('Welcome');
}

By using && between two conditions, we are saying that only if these two conditions are true, must the code between the braces execute.

Or Operator: ||

Check if either are conditions are satisfied.

Example:

if(firstName=='John' || lastName=='Smith')
{
alert('Welcome');
}

By using || between two conditions, we are saying that if either of these two conditions are true, must the code between the braces execute.

Not Operator: !

Check if conditions are not the case.

Example:

if(!(firstName=='John'))
{
alert('Welcome');
}

We are saying that if firstName is not John, the conditions evaluates to true, then the code between the braces must execute.