Name
Window.alert( ) — display a message in a dialog box
Availability
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
that the user can click to dismiss the dialog box.
On Windows platforms, the dialog box displayed by alert( )
is modal, and JavaScript execution pauses until the user
dismisses it. In Netscape 4 on Unix platforms, however, the
alert( )
dialog box is nonmodal, and execution
continues uninterrupted.
Usage
Perhaps the most common use of the alert( )
method
is to display error messages when the user’s
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 “Welcome to
my home page” or “You are the 177th visitor this
week!”
Note that the message
displayed in the dialog box is a string of plain text, not formatted HTML. You can use the newline character “\n” in your strings to break your message across ...
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