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JavaScript Window method: alert()

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The alert() method (when applied to Window objects in the JavaScript BOM) displays text in an alert box.

 

It has the following syntax with the following parameters. It does not return a value.

 

window.alert(message)

 

Parameter

Required / Optional

Description

message

Optional

String specifying text to display in an alert box

 

EXAMPLE:


HTML USED IN THIS EXAMPLE:
<!DOCTYPE html>
<html> <!-- Copyright (c) Nematrian Limited 2018 -->
<head></head>
<body>
try clicking on this
<span style="background-color: yellow;" onclick="myOnclick()">element</span>
(it should create a window alert)<br>

<script>
function myOnclick() {window.alert("Hello");}
</script>

</body>
</html>

FUNCTION THAT MAY ASSIST IN TESTING WHETHER FEATURE IS SUPPORTED:
function isSupportedJavaScriptMethodWindowAlert() {
  return !!window.alert;
}


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