How to use alert in js

The alert() function in JavaScript is used to pop up a message window in the browser to display the specified message. Syntax: alert(message); Parameters: message - the message to be displayed. Return value: None. Usage: Will cause script execution to be interrupted until the user closes the window. Applies to browser environment only.

Usage of alert() function in JavaScript

Short answer:

The

alert() function in JavaScript is used to pop up a message window in the browser to display the specified message.

Details:

• Grammar:

<code>alert(message);</code>

• Parameters:

  • message: The message to be displayed. Can be a string, number, or any other JavaScript value.

• Return value:

  • alert() The function has no return value.

• Usage:

  • To pop up a message window in the browser, you can use alert() Function. For example:

<code>alert("你好，世界！");</code>

This will display a window in the browser with the message "Hello, world!"

• Note:

  • alert() function will prevent the execution of the script until the user closes the window .
  • alert() The function is only applicable to the browser environment.
  • If you want to display more complex or interactive messages, it is recommended to use the confirm() or prompt() function.

Example:

The following is a sample code using the alert() function:

<code class="html"><button onclick="alertMessage()">点击我</button>

<script>
function alertMessage() {
  alert("你点击了我！");
}
</script></code>

When the button is clicked, a window will pop up with the message "You clicked me!"

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