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CSSStyleDeclaration JS Conversion


Window alert()

Example

Display an alert box:

alert("Hello! I am an alert box!!");
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More examples below.


Definition and Usage

The alert() method displays an alert box with a message and an OK button.

The alert() method is used when you want information to come through to the user.

Note

The alert box takes the focus away from the current window, and forces the user to read the message.

Do not overuse this method. It prevents the user from accessing other parts of the page until the alert box is closed.

See Also:

The confirm() Method

The prompt() Method


Syntax

alert(message)

Parameters

Parameter Description
message Optional.
The text to display in the alert box.

Return Value

NONE


More Examples

Alert box with line-breaks:

alert("Hello\nHow are you?");
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Alert the hostname of the current URL:

alert(location.hostname);
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Browser Support

alert() is supported in all browsers:

Chrome IE Edge Firefox Safari Opera
Yes Yes Yes Yes Yes Yes