JS Input Output – Schools

Beside using html and javascript file, to test javascript you can use tools in Firefox or Chrome Web Browser. In firefox just click : Tools -> Web Developer -> Web Console. Then type alert(“Alert From Web Console”) . In Chrome click : icon in the right top -> More Tools -> Developer Tools -> Console -> Console then type alert(“Alert From Console”);

Output

To show output the easy way is using alert , document.write and console.log . An alert is a box which popup to give warning / message to user. The example code is :

alert("Hello World, This is Alert");

To show console.log you can use in Firefox : Tools -> Web Developer -> Web Console. Then type :

console.log("This is console");

It’s very usefull if you want to debug your javascript code.

document.write("This is from document write");

Input

For input you can use prompt and confirm . The prompt is a pop up dialog/box which asking for text input . You can use like this :

prompt("How old are you");

   Confirm is command to asking user input by asking yes or no question. Here is example using it : 
 confirm("Do you like the president ?");


<!DOCTYPE html>
<html>
<head>
<title>Easy Input Output in Javascript</title>
</head>
<body>

<h1>Using Input Output in Javascript</h1>
<p>Using alert and console.log</p>
<pre><code>
    alert("Hello World, This is Alert");
    console.log("Hello World in Web Console");
</code></pre>
<p>Using prompt and confirm</p>
<pre><code>
    prompt("How old are you ?");
    confirm("Do you like the president ?");
</code></pre>
<script>
    // OUTPUT
    alert("Hello World, This is Alert");
    console.log("Hello World in Web Console");
    document.write("Hello From Document Write");
    
    // INPUT
    prompt("How old are you ?");
    confirm("Do you like the president ?");
</script>
</body>
</html>

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