MACROMEDIA FLASH 8-ACTIONSCRIPT 2.0 LANGUAGE, Справочник

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210 ActionScript language elements
for statement
for( init ; condition ; next ) {
statement(s);
}
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.
Availability: ActionScript 1.0; Flash Player 5
Parameters
init
- An expression to evaluate before beginning the looping sequence; usually an
assignment expression. A
var
statement is also permitted for this parameter.
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); // 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
The following example shows that curly braces ({}) are not necessary if only one statement
will execute:
var sum:Number = 0;
for (var i:Number = 1; i <= 100; i++)
sum += i;
trace(sum); // output: 5050
See also
++ increment operator