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while

while, loop

Availability

Flash Player 4.

Usage

    while(condition) {
    	statement(s);
    }

Parameters

`condition` The expression that is reevaluated each time the `while` action is executed. If the statement evaluates to `true`, the `statement(s)` is run.

`statement(s)` The code to execute if the condition evaluates to `true`.

Returns

Nothing.

Description

Action; tests an expression and runs a statement or series of statements repeatedly in a loop as long as the expression is `true`.

Before the statement block is run, the `condition` is tested; if the test returns `true`, the statement block is run. If the condition is `false`, the statement block is skipped and the first statement after the `while` action's statement block is executed.

Looping is commonly used to perform an action while a counter variable is less than a specified value. At the end of each loop, the counter is incremented until the specified value is reached. At that point, the `condition` is no longer `true`, and the loop ends.

The `while` statement performs the following series of steps. Each repetition of steps 1-4 is called an iteration of the loop. The `condition` is retested at the beginning of each iteration, as in the following steps:

1 | The expression `condition` is evaluated.
2 | If `condition` evaluates to `true` or a value that converts to the Boolean value `true`, such as a nonzero number, go to step 3.
| Otherwise, the `while` statement is completed and execution resumes at the next statement after the `while` loop.
3 | Run the statement block `statement(s)`.
4 | Go to step 1.

Example

This example duplicates five movie clips on the Stage, each with a randomly generated x and y position, `xscale` and `yscale`, and `_alpha` property to achieve a scattered effect. The variable `foo` is initialized with the value 0. The `condition` parameter is set so that the `while` loop will run five times, or as long as the value of the variable `foo` is less than 5. Inside the `while` loop, a movie clip is duplicated and `setProperty` is used to adjust the various properties of the duplicated movie clip. The last statement of the loop increments `foo` so that when the value reaches 5, the `condition` parameter evaluates to `false`, and the loop will not be executed.

    on(release) {
    	foo = 0;
    	while(foo < 5) {
    		duplicateMovieClip("_root.flower", "mc" + foo, foo);
    		setProperty("mc" + foo, _x, random(275));
    		setProperty("mc" + foo, _y, random(275));
    		setProperty("mc" + foo, _alpha, random(275));
    		setProperty("mc" + foo, _xscale, random(200));
    		setProperty("mc" + foo, _yscale, random(200));
    		foo++;
    	}
    }

See also

`do while`, `continue`, `for`, `for..in`