Boolean data type -- Flash CS3

A Boolean value is one that is either true or false. ActionScript also converts the values true and false to 1 and 0 when appropriate. Boolean values are most often used with logical operators in ActionScript statements that make comparisons to control the flow of a script.

The following example loads a text file into a SWF file, and displays a message in the Output panel if the text file does not load correctly, or the parameters if it does load successfully. See the comments in the code example for more details.

var my_lv:LoadVars = new LoadVars();
//success is a Boolean value
my_lv.onLoad = function(success:Boolean) {
    //if success is true, trace monthNames
    if (success) {
        trace(my_lv.monthNames);
    //if success is false, trace a message
    } else {
        trace("unable to load text file");
    }
};
my_lv.load("http://www.helpexamples.com/flash/params.txt");

The following example checks that users enter values into two TextInput component instances. Two Boolean variables are created, userNameEntered and isPasswordCorrect, and if both variables evaluate to true, a welcome message is assigned to the titleMessage String variable.

// Add two TextInput components, a Label, and a Button component on the Stage.
// Strict data type the three component instances
var userName_ti:mx.controls.TextInput;
var password_ti:mx.controls.TextInput;
var submit_button:mx.controls.Button;
var welcome_lbl:mx.controls.Label;

//Hide the label
welcome_lbl.visible = false;

// Create a listener object, which is used with the Button component.
// When the Button is clicked, checks for a user name and password.
var btnListener:Object = new Object();
btnListener.click = function(evt:Object) {
    // Checks that the user enters at least one character in the TextInput
    // instances and returns a Boolean true/false.
    var userNameEntered:Boolean = (userName_ti.text.length > 0);
    var isPasswordCorrect:Boolean = (password_ti.text == "vertigo");
    if (userNameEntered && isPasswordCorrect) {
        var titleMessage:String = "Welcome " + userName_ti.text + "!";
        welcome_lbl.text = titleMessage;
        //display the label
        welcome_lbl.visible = true;
    }
};
submit_button.addEventListener("click", btnListener);