MACROMEDIA FLASH MX 2004-ACTIONSCRIPT LANGUAGE, Reference

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for 301
for
Availability
Flash Player 5.
Usage
for( init; condition; next ) {
statement(s);
}
Parameters
init
An expression to evaluate before beginning the looping sequence; usually an assignment
expression. A
var
statement is also permitted for this parameter.
condition
An expression that evaluates to
true
or
false
. The condition is evaluated before
each loop iteration; the loop exits when the condition evaluates to
false
.
next
An expression to evaluate after each loop iteration; usually an assignment expression using
the increment (
++)
or decrement (
--
) operators.
statement(s)
An instruction or instructions to execute within the body of the loop.
Description
Statement; evaluates the
init
(initialize) expression once and then starts a looping sequence. The
looping sequence begins by evaluating the
condition
expression. If the
condition
expression
evaluates to true,
statement
is executed and the
next
expression is evaluated. The looping
sequence then begins again with the evaluation of the
condition
expression.
The curly braces (
{}
) used to enclose the block of statements to be executed by the
for
statement
are not necessary if only one statement will execute.
Example
The following example uses
for
to add the elements in an array:
var my_array:Array = new Array();
for (var i:Number = 0; i<10; i++) {
my_array[i] = (i+5)*10;
//trace(my_array[i]);
}
trace(my_array); // output: 50,60,70,80,90,100,110,120,130,140
The following example uses
for
to perform the same action repeatedly. In the code, the
for
loop
adds the numbers from 1 to 100.
var sum:Number = 0;
for (var i:Number = 1; i<=100; i++) {
sum += i;
}
trace(sum); // output: 5050
CHAPTER 2
ActionScript Language Reference