W3Schools.com


  
HOME HTML CSS XML JAVASCRIPT ASP PHP SQL MORE... REFERENCES | EXAMPLES | FORUM | ABOUT

JavaScript Comparison and Logical Operators

« Previous Next Chapter »

Comparison and Logical operators are used to test for true or false.


Comparison Operators

Comparison operators are used in logical statements to determine equality or difference between variables or values.

Given that x=5, the table below explains the comparison operators:

Operator Description Example
== is equal to x==8 is false
=== is exactly equal to (value and type) x===5 is true
x==="5" is false
!= is not equal x!=8 is true
> is greater than x>8 is false
< is less than x<8 is true
>= is greater than or equal to x>=8 is false
<= is less than or equal to x<=8 is true


How Can it be Used

Comparison operators can be used in conditional statements to compare values and take action depending on the result:

if (age<18) document.write("Too young");

You will learn more about the use of conditional statements in the next chapter of this tutorial.


Logical Operators

Logical operators are used to determine the logic between variables or values.

Given that x=6 and y=3, the table below explains the logical operators:

Operator Description Example
&& and (x < 10 && y > 1) is true
|| or (x==5 || y==5) is false
! not !(x==y) is true


Conditional Operator

JavaScript also contains a conditional operator that assigns a value to a variable based on some condition.

Syntax

variablename=(condition)?value1:value2 

Example

greeting=(visitor=="PRES")?"Dear President ":"Dear ";

If the variable visitor has the value of "PRES", then the variable greeting will be assigned the value "Dear President " else it will be assigned "Dear".


« Previous Next Chapter »


Make your web applications look like a million bucks

FusionCharts   

Most web applications today use boring methods to present data to their viewers using grids or simple HTML tables. FusionCharts induces "life" into the web applications by converting monotonous data into lively charts, gauges & maps.

FusionCharts works with all technologies like ASP, ASP.NET, PHP, ColdFusion, Ruby on Rails, JSP, HTML pages etc. and connects to any database to render animated & interactive charts. It takes less than 15 minutes and no expertise whatsoever to build your first chart and just a glance of it to captivate your audience. This fact is endorsed by our 17,000 customers and 330,000 users which include a majority of the Fortune 500 companies. And yeah, your applications could look like a million bucks by spending just $199.

So go ahead, download your copy of FusionCharts and start "wow-ing" your customers now!


 
WEB HOSTING
Best Web Hosting
PHP MySQL Hosting
Top 10 Web Hosting
UK Reseller Hosting
Web Hosting
Top Web Hosting
$1 Domain Sale
WEB BUILDING
XML Editor – Free Trial!
FREE Flash Website
6,000+ HTML Templates
Download now (FREE)
Advertise on Google
Stand out on Google search and maps Click Here
W3SCHOOLS EXAMS
Get Certified in:
HTML, CSS, JavaScript, XML, PHP, and ASP
W3SCHOOLS BOOKS
New Books:
HTML, CSS
JavaScript, and Ajax
STATISTICS
Browser Statistics
Browser OS
Browser Display
SHARE THIS PAGE