Understanding Expressions

An expression can be a variable, text, numbers and operator or any combination of the above. The important thing to remember that an expression always evaluates to a value. This can be either a string, number or boolean value.

In actionscript an expression has many uses. One of the more obvious ones is setting the value of a variable. In this case we are assigning the variable "counter" the value 2. The expressions have been highlighted in red.

Set Variable: "Counter" = 2

Another example of using an expression is evaluating a variable. Here we have the variable "firstname" with the value of "Abul". The variable "greeting" then evaluates to "Welcome Abul, to my website",

Set Variable: "firstname" = "Abul"
Set Variable: "greeting" = "Welcome" & firstname & ", to my website"

Here is another example which jumps the playhead to frame 9,

Set Variable: "frame" = 3
Go To and Play (frame + 6)

Finally this example is an access script. This script ulitmately outputs "Access Denied" because the variable "lastname" equates to "smithy" and not "smith".

Set Variable: "firstname" = "john"
Set Variable: "lastname" = "smithy"
If ((firstname = "john") and (lastname = "smith"))
    Set Variable: "output" = "Hi Mr" & lastname
    Begin Tell Target ("/membersarea")
        Go to and play("enter")
    End Tell Target
Else
    Set Variable: "output" = "Access Denied"
    Go to and play("start")
End If