More on JavaScript Array Objects - Slice Them Taters
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Slice() is another useful object. It consists of two parameters, one of which is required (start) and the other of which is not (end). It is used to retrieve and return elements in an array starting from the index number you specify and ending either where you specify, or at the end of the array if you do not specify an ending number.
In this first example we are going to slice() out some names from our fat people array. Before we do, however, just remember: the first element in an array starts with index number 0; so therefore, the second element would be 1, the third 2, and so forth:
<html>
<body>
<script type="text/javascript">
var fat = new Array(4);
fat[0] = "John Candy";
fat[1] = "Me";
fat[2] = "Valerie Bertinelli";
fat[3] = "Steven Segal";
document.write("Here is a list of fat dudes:");
document.write("<br />" + "<br />");
document.write(fat + "<br />" + "<br />");
document.write("These two are the hottest:" + "<br />");
document.write(fat.slice(1,3) + "<br />" + "<br />");
document.write("Here is the array again; no one was removed:" + "<br />");
document.write(fat);
</script>
</body>
</html>
Here, we have created our array of fat guys and printed them out. Next, we used slice() to print the two hottest people in the list. Note that when we typed fat.slice(1,3), it prints the elements 1 and 2, but not three, as three is the stopping point. Here is the result:
Here is a list of fat dudes:
John Candy,Me,Valerie Bertinelli,Steven Segal
These two are the hottest:
Me,Valerie Bertinelli
Here is the array again; no one was removed:
John Candy,Me,Valerie Bertinelli,Steven Segal
Note that had we not told the program to stop at 3, or specified a stopping number at all, as in the following example, it would have printed all the of the elements that appeared after index 1. Here is the code and the result:
<html>
<body>
<script type="text/javascript">
var fat = new Array(4);
fat[0] = "John Candy";
fat[1] = "Me";
fat[2] = "Valerie Bertinelli";
fat[3] = "Steven Segal";
document.write("Here is a list of fat dudes:");
document.write("<br />" + "<br />");
document.write(fat + "<br />" + "<br />");
document.write("These are the hottest:" + "<br />");
document.write(fat.slice(1) + "<br />" + "<br />");
document.write("Here is the array again; no one was removed:" + "<br />");
document.write(fat);
</script>
</body>
</html>
Here it prints out all of the elements, except index 0:
Here is a list of fat dudes:
John Candy,Me,Valerie Bertinelli,Steven Segal
These are the hottest:
Me,Valerie Bertinelli,Steven Segal
Here is the array again; no one was removed:
John Candy,Me,Valerie Bertinelli,Steven Segal
Next: Sort() It Out >>
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