In JavaScript, the alert() method is used to display an alert box with a specified message and an OK button. The syntax is "alert(message)"; where message is used to represent the message to be popped up on the window. The plain text displayed in the dialog box.
The operating environment of this tutorial: Windows 10 system, JavaScript version 1.8.5, Dell G3 computer.
What is the usage of alert in JavaScript
Definition and usage
The alert() method is used to display an alert box with a specified message and an OK button.
Syntax
alert(message)
Parameter Description
message The plain text (not HTML text) to be displayed in the pop-up dialog box on the window
The example is as follows :
<html>
<head>
<script type="text/javascript">
function disp_alert()
{
alert("我是一个消息框！")
}
</script>
</head>
<body>
<input type="button" onclick="disp_alert()" value="显示消息框" />
</body>
</html>Output result:
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