programming-for-dummies

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Designing User Interfaces
JavaScript arrays can store any type of data, such as integers, decimal
values, strings, or Boolean values like this:
var myarray = [93.42, “Hi there”, 3];
Another way to create a JavaScript array is to define the array size and then
store data in that array like this:
var myarray = new Array(x);
Here x is the size of the array, such as 4 or 9. After defining an array, you can
store items in that array like this:
myarray[2] = “This works”;
JavaScript arrays are zero-based, which means if you define an array like
this:
var myarray = new Array(2);
The array elements are numbered myarray[0], myarray[1], and
myarray[2].
Designing User Interfaces
JavaScript can retrieve data from the user by creating different types of user
interface elements, such as dialog boxes and windows. Such user interface
items can display information to the user, creating an interactive Web page.
Creating dialog boxes
The three types of dialog boxes JavaScript can create are alert, confirmation,
and prompt. An alert dialog box displays a message on the screen and gives
the user the option of closing the dialog box. A confirmation dialog box displays
a message and offers the user two or more choices. A prompt dialog
box gives users a chance to type in data.
To create an alert dialog box, you need to define the text you want displayed,
such as
alert(“Message here”);
An alert dialog box displays an OK button. As soon as the user clicks this OK
button, the alert dialog box goes away.