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Javascript - Points to Remember


What is it?
  • Client-Side Scripting Language (we send the code to the client and let them run it)
Asp.Net is sever side
  • Developed by Sun Microsystem
  • Programming Language of the web that adds interactivity to the pages
  • Only works inside a web browser to manipulate web pages. Cannot be used in windows application. Does not have access to file system, database, usb port
  • jquery - 3rd party javascript library . provide excellent cross browser functions (Microsoft product)
  • web pages have the following 3 core languages
    • html - content eg: what needs to be displayed and how
    • css - presentation eg: background color, font
    • javascript - behavior (interactivity) eg: wht happens on mouse click
  • EcmaScript 3 - 1999 has full support on IE, Firefox, chrome, opera, safari
Where to put the javascript:
  • Inline
  • In Script tag
                 

  • In another file
                     -- in original page
                   alert("hello");is in a new page - myscript.js (by convention it is .js , not necessary)

Variables in Javascript:
var name1;
name1 = value1; -- value can be string , boolean, numbers

Arrays in Javascript:
Array -- can have bool, int, string together
var name2 = [];
names2[0]=50;
names2[1]= "aditi" ;

----- or ----

var num3 = [50, "mou", true];

----- or ----

var num4 = new Array(); // arrays are objects

----- or ----

var num5 = Array(); // arrays are dynamic

----- or ----

var num6 = Array(5); // arrays of size 5
 
 
 
Example 1:
click on < a href="javascript:sayhello()"> will call sayhello function
 


 
Diff Between HTML4 and HTML5

Html 4 : 

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