Transcript campus.murraystate.edu
JavaScript
Background Developed by Brandon Eich Mid 1990s Originally called Mocha Has nothing to do with Java
Purpose Interpreted Language Utilized on multiple platforms Not designed as a standalone language Easy to incorporate in HTML Light-weight, very portable
Variables Container for storing data Dynamic Typing Must begin with a letter Can consist of numbers, letters, $ and _ Case Sensitive Variables are declared using var
Data Types String Number Boolean Array Undefined Null
If Else if (time<20) { x="Good day"; { } else x="Good evening"; }
Switch var day=new Date().getDay(); switch (day) { case 0: x="Today it's Sunday"; break; case 1: x="Today it's Monday"; break; case 2: x="Today it's Tuesday"; break; case 3: x="Today it's Wednesday";
For Loop for (var i=0;i
While and Do While while (i<5) { x=x + "The number is " + i + "
"; i++; } do { x=x + "The number is " + i + "
"; i++; } while (i<5);
Functions } Function myFunction(side1, side2) { var side3 = sqrt((side1*side1) + (side2*side2)); return side3; var ans = myFunction(side1, side2);
Objects Just Data with properties and methods Almost everything can be an Object Created by using: Person = new Object(); A property is called using: Person.age; A method is called using: Person.name.toUpperCase();
Error Handling
My First JavaScript
Example Code – Alert Message
Click the button to display an alert box.