Javascript 1

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Introduction to JavaScript •

Is a scripting language

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Interpreted from within a browser.

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Available in two formats : client-side JavaScript and serverside JavaScript.

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It is an object-based language that comes with many built-in objects.

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Is platform-independent as long as the browser is JavaScript-enabled.

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Is designed to extend the capabilities of the Web application to provide user interactivity.

INTRODUCTION TO JAVASCRIPT

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Keywords in JavaScript

3.0 Rules to follow when naming variables :

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The name must begin with a letter or an underscore.

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The rest of the name is made up of letters, numbers, or underscores.

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Do not use the reserved words in JavaScript.

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Avoid placing any spaces or punctuation in the name.

VALID

INVALID

mynumber

my number

student_no

student.no

male

*male

year2001

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(period) (must start with a number) (must start with a number)

Operators in JavaScript

symbol = + * / % ++ -== != > < >= <= && ||

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(space)

description Assign values Addition Subtraction Multiplication Division Modulus returns the remainder Increments by one Decrements by one equals not equal to greater than less than greater than or equal to less than or equal to logical AND logical OR

Hello World Program

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6.0 Window Alert

7.0 Window Prompt

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Sample Codes 1

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Sample Codes 2

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Sample Codes 3

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Sample Codes 4

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