#14 JS: create a calculator by prompt()

2021 iThome 鐵人賽

DAY 14

Modern Web

Learn & Play JavaScript -- Entry-Level Front-End Web Development系列第 14 篇

13th鐵人賽 front-end frontend javascript js

Vida Lin

2021-09-14 09:23:38

722 瀏覽

分享至

Final Calculator Design

<!DOCTYPE html>
<html>
<head>
<title>JavaScript</title>
<script type="text/javascript">

var n1=prompt("Please key in a random number.","e.g.123"); 
var n2=prompt("Please key in a random number.","e.g.123");
var result=n1*n2;
alert(result);

</script>
</head>
</html>

Design a Calculator

prompt() is a dialogue box that user can key in values, and it will close until the user submit or cancel.

Basing on the rule, we can separate the user behavior into steps, like:
input: prompt(default value or an example) → operate → output: alert(data)

For example, to create a simple calculator...

var n1=prompt("Please key in a random number." , "7");

var n2=prompt("Please key in a random number." , "7");

var result=n1*n2;
alert(result);

=> The result is 49.

Music of Today: 馬祖小夜曲 Ma-Chu Song by MC Hotdog 熱狗 Feat. Agota

Like/Share/Follow

Feel free to comment and share your ideas below to learn together!
If you guys find this article helpful, please kindly do the writer a favor — LIKE this article.