MACROMEDIA FLASH MX, Reference

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52 Chapter 2: ActionScript Language Reference
?: (conditional)
Availability
Flash Player 4.
Usage
expression1 ? expression2 : expression3
Parameters
expression1
An expression that evaluates to a Boolean value; usually a comparison expression,
such as
x < 5
.
expression2
,
expression3
Values of any type.
Returns
The value of
expression2
or
expression3
.
Description
Operator; instructs Flash to evaluate
expression1
, and if the value of
expression1
is
true
, it
returns the value of
expression2
; otherwise it returns the value of
expression3
.
For more information, see “Operator precedence and associativity” in Using ActionScript in Flash .
Example
The following statement assigns the value of variable
x
to variable
z
because
expression1
evaluates to
true
:
var x:Number = 5;
var y:Number = 10;
var z = (x < 6) ? x: y;
trace (z); // returns 5
The following example shows a conditional statement written in shorthand:
var timecode:String = (new Date().getHours()<11) ? "AM" : "PM";
trace(timecode);
The same conditional statement could also be written in longhand, as shown in the following
example:
if (new Date().getHours()<11) {
var timecode:String = "AM";
} else {
var timecode:String = "PM";
}
trace(timecode);