1. var variableName:datatype;
Variables in flash
In order to retrieve all the informationm we need to store it into variables.
The primary information storage of Actionscript.
You can declare variables on a frame in the timeline or directly on an object.
Define variables using the var keyword.
The general form to declare variables in flash:
var variableName:datatype;

2. Variables in flash variableName: any valid Identifier.
Ex) id, myVariable, x
3myVariable is invalid because it starts with a number.
Datatype: primitive data types (Number, String, Boolean).
There are other built-in data types in flash (such as Sound, Date, …)

3. Primitive Data Types Number Data Type:
It is used to store numeric data types.
Numeric types could be integers (4,5,20) or floating-point numbers (2.4,4.321)
Ex) example on declaring numeric variable:
var f1:Number;
Ex) example on declaring a variable with initialization:
var f1:Number = 5;

4. Primitive Data Types
Ex) the following example shows how to deal with number variables:
Create a new flash file
Add a button symbol into the stage.
Add text field into the stage
Use the text field property inspector to change the text type to (Dynamic Text). And, use it to give the inserted text field an instance name (myText).
Instance name is used to access the object using Action script
Text Type: Dynamic Text (can be changed during running)

5. Primitive Data Types
In the action panel of the first frame, declare a variable (x) of type Number and initialize it to 4.
In the action panel of the button, write the following action script:
On (press) {
myText.text = x*x + 2*x +4; }
Test the movie

6. Primitive Data Types Boolean Data Type:
It is used in logical operations to represent a certain state.
It could only hold two values:
true
false
Ex) var f2:Boolean = true;

7. Primitive Data Types String Data Type:
It used to store data as a text ( a sequence of characters).
Ex) “This is some text”
String in flash should be enclosed within double quotation (“”)
Ex) to declare a variable (s) of type String and store “some text” in it:
var s:String = “some text”;

8. Primitive Data Types
Each character in a string has an index.
The indices of characters are numbered (0,1,2,3,…) from left to right.
The string characters created in the previous example have indices as follows:
s o m e t e x t

9. Primitive Data Types Functions to manipulate string: charAt(i);
This function returns a character from a string found in index (i)
i: integer number represent an index.
Ex) var s:String = “some text”;
trace(s.charAt(2)); // m
indexOf(str);
This function returns the index of the passed (str) within the text.
Ex) trace(s.indexOf(“m”)); // 2

10. Primitive Data Types length; substr(index,length);
Returns the number of characters in the string.
Ex) trace(s.length); // 9
substr(index,length);
Returns a part of the string as specified in the parameters.
index: an integer gives the starting point of the taken part.
length: the number of characters to take starting at (index).
Ex) trace(s.substr(1,5)); // ome t
s o m e t e x t
index

11. Primitive Data Types toUpperCase(); toLowerCase();
Returns the capital letter representation of the string.
toLowerCase();
Returns the lower letter representation of the string.

12. String Example
Ex) this example illustrate how to build a flash program to read string value from keyboard, convert it to its capital representation, and print the result in a text field on the stage:
Create a flash file.
Insert a text field on the stage, convert its type to (Input Text) and give it an instance name (txtinput)
When you change the type of a text field to (Input Text), you can insert text values into it at runtime from keyboard.
Giving an instance name to a text fields allow us to access it using action script.

13. String Example
Insert a text field on the stage. Convert its type to dynamic and give it an instance name (txtoutput)
Add a button on the stage. Insert the text (Convert to Capital) in the button.
In the action pane of the button, add the following script:
on(press) {
var s:String;
s = txtinput.text;
txtoutput.text = s.toUpperCase(); }
To take the text inserted into (txtinput) and assign it to (s)
To make return the capital letter representation of s. Then assign it to (txtoutput)

14. Global variable
Global variables are visible to every timeline and every scene in your flash file.
To declare (or create) a variable with global scope, use the _global identifier before the variable name and do not use the var keyword.
Ex) _global.myName = “globalvar";

15. Flash Sounds There are two ways to add sounds to our flash file:
import a sound file (in whatever format the flash editor can handle, e.g. mp3, wav... etc), and pull it onto the stage.
Ex)
create new flash file
Go to FileImportImport to Library
Choose the sound file from your computer, and click open.
You can notice that your sound file was added to your library.
Now, Drag and drop that flash symbol into the stage.
Test the movie

16. Flash Sounds
if you want to have better control in playing the sound file, you may need some actionscripts.
starting and stopping the music by pressing the corresponding button.
Ex) This example illustrates how to control sounds inside flash program.
Open a new file in the Flash
Import a sound file into the library.
MRC on the imported sound(in the library window; you may need to open the library window first), and select linkage on the pop up menu.

17. Flash Sounds
check the export to actionscript option and type the name "mysound" in the textbox.
This will assign an id to the imported sound, so later on the actionscripts can refer to it.
Ok, back to the main stage. Select the first frame on the timeline, open the action window and put the following code in it:
var snd:Sound = new Sound(); snd.attachSound("mysound");
Basically, the above code will create a sound object and attach the imported sound file to it.
insert a (play) button in the stage and write the following code in the action pane of it:

18. Flash Sounds on(release) { _root.snd.start(0, 10); }
Action is performed when releasing the button
_root: to access every object in the main timeline
Start(0,10): This will start playing the sound (and loops 10 times) when the button is clicked.

19. Flash Sounds
Repeat step 6 to create the stop button but associated with the following actionscritps instead:
on(release) { _root.snd.stop(); }
Stop(): to stop the sound