Macromedia flash 8-learning flash lite 1.x actionscript User Manual

Using the eval() function

The

eval()

function lets you dynamically reference variables and movie clip instances at

runtime. The

eval()

function takes a string expression as a parameter and returns either the

value of the variable represented by that expression or a reference to a movie clip.

For example, the following code evaluates the value of the

name

ActionScript variable and

assigns the result to

nameValue

name = "Jack";
nameValue = eval("name");
// result: nameValue = "Jack"

The

eval()

function is often used with

for()

loops and the

add

(string concatenation)

operator to create string-based arrays, because Flash Lite doesn’t support native array data
structures. For more information, see

You can also use

eval()

to reference movie clip instances by name. For example, suppose you

had three movie clips named

clip1

clip2

, and

clip3

. The following

for()

loop increments

the x position of each clip by 10 pixels:

for(index = 1; index <= 3; index++) {

eval("clip" add index)._x += 10

}