W3Schools

home HOME

JS Basic
JS HOME
JS Introduction
JS How To
JS Where To
JS Statements
JS Comments
JS Variables
JS Operators
JS Comparisons
JS If...Else
JS Switch
JS Popup Boxes
JS Functions
JS For Loop
JS While Loop
JS Break Loops
JS For...In
JS Events
JS Try...Catch
JS Throw
JS onerror
JS Special Text
JS Guidelines

JS Objects
JS Objects Intro
JS String
JS Date
JS Array
JS Boolean
JS Math
JS RegExp
JS HTML DOM

JS Advanced
JS Browser
JS Cookies
JS Validation
JS Animation
JS Image Maps
JS Timing
JS Create Object
JS Summary

Examples/Quiz
JS Examples
JS Object Examples
JS DOM Examples
JS Quiz

JS References
JS Objects
JS HTML DOM

Selected Reading
Web Statistics
Web Glossary
Web Hosting
Web Quality

W3Schools Forum

Helping W3Schools

JavaScript Operators

previous next

The operator = is used to assign values.

The operator + is used to add values.


The assignment operator = is used to assign values to JavaScript variables.

The arithmetic operator + is used to add values together.

y=5;
z=2;
x=y+z;

The value of x, after the execution of the statements above is 7.


JavaScript Arithmetic Operators

Arithmetic operators are used to perform arithmetic between variables and/or values.

Given that y=5, the table below explains the arithmetic operators:

Operator Description Example Result
+ Addition x=y+2 x=7
- Subtraction x=y-2 x=3
* Multiplication x=y*2 x=10
/ Division x=y/2 x=2.5
% Modulus (division remainder) x=y%2 x=1
++ Increment x=++y x=6
-- Decrement x=--y x=4


JavaScript Assignment Operators

Assignment operators are used to assign values to JavaScript variables.

Given that x=10 and y=5, the table below explains the assignment operators:

Operator Example Same As Result
= x=y   x=5
+= x+=y x=x+y x=15
-= x-=y x=x-y x=5
*= x*=y x=x*y x=50
/= x/=y x=x/y x=2
%= x%=y x=x%y x=0


The + Operator Used on Strings

The + operator can also be used to add string variables or text values together.

To add two or more string variables together, use the + operator.

txt1="What a very";
txt2="nice day";
txt3=txt1+txt2;

After the execution of the statements above, the variable txt3 contains "What a verynice day".

To add a space between the two strings, insert a space into one of the strings:

txt1="What a very ";
txt2="nice day";
txt3=txt1+txt2;

or insert a space into the expression:

txt1="What a very";
txt2="nice day";
txt3=txt1+" "+txt2;

After the execution of the statements above, the variable txt3 contains:

"What a very nice day"


Adding Strings and Numbers

Look at these examples:

x=5+5;
document.write(x);

x="5"+"5";
document.write(x);

x=5+"5";
document.write(x);

x="5"+5;
document.write(x);

Try it yourself.

The rule is:

If you add a number and a string, the result will be a string.


previous next


Learn XML with <oXygen/> XML Editor - Free Trial!

oXygen - Probably The World's Best XML Editor   

oXygen helps you learn to define, edit, validate and transform XML documents. Supported technologies include XML Schema, DTD, Relax NG, XSLT, XPath, XQuery, CSS.

Understand in no time how XSLT and XQuery work by using the intuitive oXygen debugger!

Do you have any XML related questions? Get free answers from the oXygen XML forum and from the video demonstrations.

Download a FREE 30-day trial today!




Jump to: Top of Page or HOME or Printer Friendly Printer friendly page

W3Schools provides material for training only. We do not warrant the correctness of its contents. The risk from using it lies entirely with the user. While using this site, you agree to have read and accepted our terms of use and privacy policy.

Copyright 1999-2008 by Refsnes Data. All Rights Reserved.

Validate Validate W3C-WAI level A conformance icon W3Schools was converted to XHTML in December 1999
SITE SEARCH
 
About W3Schools
W3Schools Forum
Shopping Cart
ASP.NET
Shopping Cart
WEB HOSTING
$15 Domain Name
Registration
Save $20 / year!
UK Domain Names
UK Web Hosting

Alojamiento Web
Buy UK Domain Names
Register Domain Names
Cheap Domain Names
Cheap Web Hosting
Best Web Hosting
Domain Name Registration
PHP MySQL Hosting
Top 10 Web Hosting
Web Hosting Providers
Web Hosting Company
UK Web Hosting
UK Reseller Hosting
Web Hosting
WEB BUILDING
Website Templates
Flash Templates
Website Builder
Internet Business Opportunity
Custom Programming
FREE Trial or Demo
Web Content Manager
Forms,Web Alerts,RSS
Ecommerce Software
XMLSpy® XML Editor
Azbuz Blog
SHOPPING
UK Wholesalers
UK Wholesale
UAE Dubai Property
Private Student Loans
UK Dropshippers & Wholesalers Directory
EDUCATION
US Web Design Schools
HTML Exam
YELLOW PAGES
www.nettkatalogen.no
www.gulex.dk
www.gulex.se
www.gelbex.de
www.teloos.fi
www.teloos.fr
www.teloos.co.uk
www.teloos.at
www.teloos.de