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<TITLE>Using Function</TITLE> The following HTML code demonstrates the use of Alert Box in JavaScript:
<SCRIPT>
Code
function changeColour() Create a web page to demonstrate the use of Alert Box in JavaScript.
6
{
document.body.style.backgroundColor = "lightblue"; <!DOCTYPE HTML>
} <HTML>
</SCRIPT> <HEAD>
</HEAD> <TITLE>Form Submission Alert</TITLE>
<SCRIPT>
<BODY>
{
<H1>Click the Button to Change the Background Colour</H1>
alert("Please fill out all fields.");
<BUTTON onclick="changeColour()"> Change Colour </BUTTON>
}
</SCRIPT>
</SCRIPT>
</BODY>
</HEAD>
</HTML>
<BODY>
The output of the preceding HTML code is as follows:
<H1>Contact Form</H1>
<FORM>
<LABEL>Name:</LABEL>
<INPUT TYPE="TEXT" ID="NAME" NAME="NAME" REQUIRED><BR><BR>
<LABEL>Email:</LABEL>
<INPUT TYPE="EMAIL" ID="EMAIL" NAME="EMAIL" REQUIRED><BR><BR>
<BUTTON TYPE="SUBMIT">Submit</BUTTON>
</FORM>
The function changes the background colour of the web page to light blue using JavaScript. </BODY>
PRIVACY PRACTICES </HTML>
The output of the preceding HTML code is as follows:
Developers should always sanitize data. This means they need to ensure that the data a user
enters into a website is safe before using it.
JAVASCRIPT POPUP BOXES
The JavaScript popup boxes are used to interact with users by displaying messages or requesting
input. There are three main types of popup boxes: Alert Box, Confirm Box and Prompt Box.
ALERT BOX CONFIRM BOX
The Alert box displays a message and can only be closed by the user clicking the OK button. A Confirm Box asks the user to confirm or cancel an action. If the user clicks OK, it returns true;
This box is often used to show important information or warnings. The alert() function is used to if Cancel is clicked, it returns false. The confirm() function is used to trigger the confirm box.
trigger the alert box. It’s commonly used for actions like deleting or submitting forms.
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JavaScript for Beginners
