انها محاولة لنفسك - JavaScript Reference doc

<!DOCTYPE html>
<html>
<body>

<script id="myFirstScript">
document.write("Hello World!");
</script>

<p>Click the button to display the id of each script element in the document.</p>

<button type="button" onclick="myFunction()">Try it</button>

<p id="demo"></p>

<script id="mySecondScript">
function myFunction() {
   var x = document.scripts;
   var txt = "";
   var i;
   for (i = 0; i < x.length; i++) {
   txt = txt + x[i].id + "<br>";
   }
   document.getElementById("demo").innerHTML = txt;
}
</script>

</body>
</html>