We left off a while back discussing the various built-in Date Objects that JavaScript has to offer. Prior to that we talked about String Objects and JavaScript Events. Here and now, we are going to go over the Array Objects, which we can use to manipulate arrays. We will start off by viewing a table of them and the definitions of each. After that we will begin with the concat() method and try our best to work our way through the remaining thirteen.
JavaScript: Array Objects - Pop() and Lock (Page 3 of 5 )
If you have read any of my other articles on methods and functions for other languages, then you will know that JavaScript shares many of them. For instance, I just wrote an article on Perl that uses the pop(), push(), shift(), unshift(), and splice methods (to name a few), which have the same use in Perl as they do in JavaScript.
As our table indicated earlier, we use pop() when we want to remove and return the right most (or end) element in an array. Here is the code:
<html>
<body>
<script type="text/javascript">
var bboys = new Array(3);
bboys[0] = "Greg";
bboys[1] = "Bobby";
bboys[2] = "Peter";
document.write(bboys + "<br />");
document.write(bboys.pop() + "<br />");
document.write(bboys);
</script>
</body>
</html>
This code is pretty self-explanatory. First we assign the bboys array some values. Then we write out the values to the screen, and remove the end element from the array using pop(), printing out the removed element. Finally, we print out the values of bboys once more to show that “Peter” has been removed.
Here is the result:
Greg,Bobby,Peter Peter Greg,Bobby
Note that we could keep popping the array until it was empty:
<html>
<body>
<script type="text/javascript">
var bboys = new Array(3);
bboys[0] = "Greg";
bboys[1] = "Bobby";
bboys[2] = "Peter";
document.write(bboys + "<br />");
document.write(bboys.pop() + "<br />");
document.write(bboys.pop() + "<br />");
document.write(bboys.pop() + "<br />");
document.write(bboys);
</script>
</body>
</html>
Each time we pop() the array, the last element gets removed until there are no values left in the array. Here is how it prints out (note that the final document.write prints nothing, as nothing remains to be printed):
JavaScript 
/ 5 
More on JavaScript Array Objects
