<script>...</script> tag set. tag. Script with src,
<script src="my-script.js" type="text/javascript"></script>The purpose is to define functions, objects, and variables. Functions will later be triggered by buttons, other user events, inline script tags with body content, etc. script with body content
<script type="text/javascript">JavaScript code</script>
Purpose is to define functions, objects, and variables. To directly invoke code that will run as page loads, to output HTML content built by JavaScript Don't use this approach for defining functions or for doing things that could be done in external files. Slower (no browser caching) and less reusable.
Learn By Example-1:
//Example (phish.js)
function getMessage() {
var amount = Math.round(Math.random() * 100000);
var message =
"You won $" + amount + "!\n" +
"To collect your winnings, send your credit card\n" +
"and bank details to oil-minister@phisher.com.";
return(message);
}
function showWinnings1() {
alert(getMessage());//"alert" pops up dialog box
}
function showWinnings2() {
document.write("<h1><blink>" + getMessage() +
"</blink></h1>");
//"document.write" inserts text into page at current location.
//Example (loading-scripts.html)
<!DOCTYPE ...><html xmlns="http://www.w3.org/1999/xhtml">
<head><title>Loading Scripts</title>
...
<script src="./scripts/phish.js"//Loads script from previous page
type="text/javascript"></script>
</head>
<body>
...
<input type="button" value="How Much Did You Win?"
onclick='showWinnings1()'/>
//Calls showWinnings1 when user presses
//button. Puts result in dialog box.
...
<script type="text/javascript">showWinnings2()</script>
//Calls showWinnings2 when page is loaded in
//browser. Puts result at this location in page.
...
</body></html>
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