User Guide

set variable 201
set variable
Availability
Flash Player 4.
Usage
set("variableString", expression)
Parameters
variableString
A string that names a variable to hold the value of the expression parameter.
expression A value assigned to the variable.
Returns
Nothing.
Description
Statement; assigns a value to a variable. A variable is a container that holds data. The container is
always the same, but the contents can change. By changing the value of a variable as the SWF file
plays, you can record and save information about what the user has done, record values that
change as the SWF file plays, or evaluate whether a condition is
true or false.
Variables can hold any data type (for example, String, Number, Boolean, Object, or MovieClip).
Strict data typing is not supported inside a
set statement. If you use this statement to set a
variable to a value whose data type is different from the data type associated with the variable in a
class file, no compiler error is generated.
A subtle but important distinction to bear in mind is that the parameter
variableString is a
string, not a variable name. If you pass an existing variable name as the first parameter to
set()
without enclosing the name in quotation marks (
""), the variable is evaluated before the value of
expression is assigned to it. For example, if you create a string variable named myVariable and
assign it the value “Tuesday,” and then forget to use quotation marks, you will inadvertently create
a new variable named
Tuesday that contains the value you intended to assign to myVariable:
var myVariable:String = "Tuesday";
set (myVariable, "Saturday");
trace(myVariable); // outputs Tuesday
trace(Tuesday); // outputs Saturday
You can avoid this situation by using quotation marks (""):
set ("myVariable", "Saturday");
trace(myVariable); //outputs Saturday
Example
In the following example, you assign a value to a variable. You are assigning the value of "Jakob"
to the
name variable.
set("name", "Jakob");
trace(name);
CHAPTER 5
ActionScript Core Language Elements