- Learn what is an Array, Why do we use them, and how do we create them.
- Different Properties and Methods of the Array Object
- Using Arrays with Loops
- Using Associative Arrays
Objectives of
Today’s SIG:
Creating An Array:
What is an Array?
Array = a way of storing data of similar types for
easy access in a script. A user defined
object that is accessed in a different way than other objects are accessed.
Why Arrays are
Useful?
To make it easier
to access the stored information.
Defining and
Accessing Arrays
var arrayname = new
Array()
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
<html
xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>PACS
JavaScript SIG</title>
</head>
<body>
<h1>PACS
JavaScript SIG/</h1>
<script
type="text/javascript">
//Creating the
Array
var pitcher_names =
new Array("Roy Halladay","Cole Hamels","Cliff
Lee","Jonathan Pettibone");
var ws_mvp =
pitcher_names[1];
// Remember 1=2
document.write
("The MVP for the 2008 World Series was
"+ws_mvp+"</br>");
// create array and
then add to it
var infield1_name =
new Array();
infield1_name[0] =
"Kevin Frandsen";
infield1_name[1] =
"Freddy Galvis";
infield1_name[3] =
"Ryan Howard";
infield1_name[5] =
"Cesar Hernandez";
infield1_name[6] =
"Jimmy Rollins";
infield1_name[4] =
"Chase Utley";
infield1_name[2] =
"Michael Young";
infield1_name[29] =
"Andrew Schooler";
var clean_up =
infield1_name[30];
document.write("Now
batting clean up "+clean_up+"</br>");
</script>
</body>
</html>
Array Objects:
Understanding the
Properties and Methods of the Array Object.
Properties
The
Length Property
The
prototype Property
<script
type="text/javascript">
var pitcher_names =
new Array("Roy Halladay","Cole Hamels","Cliff
Lee","Jonathan Pettibone");
var infield1_name =
new Array();
infield1_name[0] =
"Kevin Frandsen";
infield1_name[1] =
"Freddy Galvis";
infield1_name[3] =
"Ryan Howard";
infield1_name[5] =
"Cesar Hernandez";
infield1_name[6] =
"Jimmy Rollins";
infield1_name[4] =
"Chase Utley";
infield1_name[2] =
"Michael Young";
// Length Property
document.write("The
infield1_name array has "+infield1_name.length+"
elements.</br>");
// Prototype
Property
Array.prototype.standing
= "Bad team";
Array.prototype.standing2
= "Good team";
document.write("Currently
the team's infield ranks
"+infield1_name.standing+"</br>");
document.write("Currently
the team's pitching ranks
"+pitcher_names.standing2+infield1_name.standing+"</br>");
//
document.write("Currently the team's pitching ranks
"+infield1_name[6].standing2+"</br>");
</script>
Methods
concat
join
sort
toString
slice
splice
pop, push, shift
and unshift
<script
type="text/javascript">
var pitcher_names =
new Array("Roy Halladay","Cole Hamels","Cliff
Lee","Jonathan Pettibone");
var infield1_name =
new Array();
infield1_name[0] =
"Kevin Frandsen";
infield1_name[1] =
"Freddy Galvis";
infield1_name[3] =
"Ryan Howard";
infield1_name[5] =
"cesar Hernandez";
infield1_name[6] =
"Jimmy Rollins";
infield1_name[4] =
"Chase Utley";
infield1_name[2] =
"Michael Young";
// Methods
// join method
var pitchers1 =
pitcher_names.join();
document.write("The
Phillies Pitching Staff: "+pitchers1+"</br>");
var pitchers2 =
pitcher_names.join(", ");
document.write("The
Phillies Pitching Staff: "+pitchers2+"</br>");
var pitchers3 =
pitcher_names.join(" : ");
document.write("The
Phillies Pitching Staff: "+pitchers3+"</br>");
// concat method
var catchers_name =
new Array ("Erik Kratz","Sebastian Valle");
var catchers1 =
catchers_name.join(", ");
document.write("The
Phillies Catchers: "+catchers1+"</br>");
var pitchers2 =
pitcher_names.join(", ");
document.write("The
Phillies Pitching Staff: "+pitchers2+"</br>");
// adding the .join
at the end
var pitch_n_catch =
pitcher_names.concat(catchers_name).join("");
document.write("00
The following will report to Camp on Feb. 21st:
"+pitch_n_catch+"</br>");
var line_up =
pitcher_names.concat(catchers_name,infield1_name);
document.write("The
following will report to Camp on March 1st:
"+line_up+"</br>");
// sort method
var infield_alpha =
infield1_name.sort();
document.write("01
Names in alphabetical order "+infield_alpha+"</br>");
var infield_alpha =
infield1_name;
document.write("01
Names in alphabetical order "+infield_alpha+"</br>");
// reverse method
var infield_rev =
infield1_name.reverse();
document.write("02
Names in reverse order "+infield_rev+"</br>");
// toString method
var pitchers3 =
pitcher_names.toString();
document.write(pitchers3+"</br>");
// slice method
var free_agents =
infield1_name.slice(0,2);
document.write("Look
who's up for free agencey: "+free_agents+"</br>");
// splice method
document.write("splice
method</br>");
var outfield_names
= new Array("Domonic Brown", "Zach Collier", "Tyson
Gillies", "Ender Inciarte", "John Mayberry",
"Laynce Nix", "Ben Revere", "Darin Ruf");
document.write("In
the Outfield: "+outfield_names+"</br>");
var outfield_out =
outfield_names.splice(2,2);
document.write("Out
of the outfield: "+outfield_out+"</br>");
document.write("In
the Outfield: "+outfield_names+"</br>");
outfield_names.splice(5,2,outfield_out);
document.write("In
the Outfield: "+outfield_names+"</br>");
// pop, push,
shift, and unshift methods
document.write("In
the Outfield1: "+outfield_names+"</br>");
var outfield1 =
outfield_names.pop();
document.write("Outfield
popped: "+outfield1+"</br>");
document.write("In
the Outfield now: "+outfield_names+"</br>");
outfield_names.push(outfield1);
document.write("In
the Outfield now: "+outfield_names+"</br>");
outfield2=outfield_names.shift();
document.write("Outfield
shifted: "+outfield2+"</br>");
document.write("In
the Outfield now: "+outfield_names+"</br>");
outfield_names.unshift(outfield2);
document.write("In
the Outfield now: "+outfield_names+"</br>");
</script>
Array Objects:
Using Arrays with
Loops
Using Associative
Arrays
//Using Arrays with
Loops
//Creating Array
Elements
var s_list = new
Array(4);
for(var count=0;
count<4; count++){
s_list[count]=window.prompt
("Enter a name","");
}
var
s_list1=s_list.toString();
document.write(s_list1+"</br>");
Next Month:
Math, Number, and
Date
