Name
Window.alert( ): display a message in a dialog box â JavaScript 1.0:
Synopsis
window.alert(message)
Arguments
-
message The plain-text (not HTML) string to display in a dialog box popped up over
window.
Description
The alert( ) method
displays the specified message to the
user in a dialog box. The dialog box contains an OK button the user can click to dismiss it.
The dialog box is typically modal, and the call to alert( ) typically blocks until the dialog
is dismissed.
Usage
Perhaps the most common use of the alert( ) method is to display error
messages when the userâs input to some form element is invalid in
some way. The alert dialog box can inform the user of the problem
and explain what needs to be corrected to avoid the problem in the
future.
The appearance of the alert(
) dialog box is platform-dependent, but it generally
contains graphics that indicate an error, warning, or alert message
of some kind. While alert( ) can
display any desired message, the alert graphics of the dialog box
mean that this method is not appropriate for simple informational
messages like âWelcome to my blogâ or âYou are the 177th visitor
this week!â
Note that the message displayed in the dialog box is a string of plain text, not formatted HTML. You can use the newline character â\nâ in your strings to break your message across multiple lines. You can also do some rudimentary formatting using spaces and can approximate horizontal rules with underscore characters, but the results depend greatly ...
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