Question

Layla just got hired as the Web developer for a small business called Axe Grinders, which sells and repairs guitars and amps. The aging rock 'n' rollers who own Axe Grinders were taking care of business by phone and mail, but they just don't have too much time on their hands for this anymore. They decided they need a Web site so they could start processing orders more efficiently, spend their time on guitars, and get the business back in black.

These guys know music inside and out, but their guitars gently weep when it comes to Web sites. They don't need no education about the Web, so they hired Layla to do the job for them.

Layla's new bosses are same as her old boss. Part of the reason they hired her was because they thought it would be nice to have a pretty woman around the office. Layla doesn't want to be paranoid, but she is determined to prove that she's got brains and she knows how to use them.

On her first day, the owners tell Layla that they'd like their site to have some high-voltage effects. And because they have sold guitars to several celebrity musicians, they want a feature that can list their customers along with the guitar types they bought — users could either select a specific customer or guitar, or they could list 'em all. The owners have seen some other sites do something like this, so they know it is possible, but they wonder if she can make it happen. They tell her it is okay if she can't handle this task — it's just another brick in the wall. They could get satisfaction with just a plain HTML site instead, even though it would have to be updated constantly.

As she's climbing the stairway to her office, Layla realizes that scripting the Customer List feature will require more than the usual predefined JavaScript objects. And she knows that the code for the Customer List feature will include a lot of repetition. She is determined to make these features work as requested. Layla knows she's got to ramble. Because even though the owners said it would be ok to have a simpler site, she would really like to impress them.

Consider this scenario and answer the following questions.

• How can Layla use JavaScript custom objects to create the Customer List feature for the Web site?
• How do custom objects help Web developers with repetitive programming tasks such as the ones in the Customer List feature?
• What other advantages do custom objects offer to Layla in this situation?
• What are the first steps Layla should take in creating a custom object for this feature?

Answer 1

1.) Layla can use JavaScript custom objects to create Customer List feature for the Web site. She can the

JavaScript Array prototype Constructor. The object may contain 2 fields that are customer name and guitar type the bought.

To prevent repitition, She can use Array prototype Constructor in javascript or array of custom objects as usual.

This is an example representation

function CustomerList(CustomerName,GuitarType) {
            this.CustomerName=CustomerName;
            this.GuitarType=GuitarType;
        }

var tmp = [new CustomerList('Customer 1','Guitar 1'), new CustomerList('Customer 2','Guitar 2')];

she can then render this to the list.

this saves a lot of repetition in the code and saves human effort and makes code organized.

Q2. A function to perform the repetitive task-in this case is required as data has to be entered a lot of times and Guitars may be of different types and many customers can buy same guitar type. So, this saves a lot of space and time and gives a healthy coding environment. The Web Developers can focus on logic more in this saved amount of time and implement better features. Special Functions can help to sort the list as per users wish.

Q3.

Layla leaves the constructor and the main coding object is uncluttered. This is the standard way of doing things in JavaScript, and all built-in constructors put their methods on their prototypes.Layla can “modify” objects after they’ve already been created. Using "this" keyword she can You can use closures and therefore private member variables.There are many patterns for implementing inheritance in JS, such as Constructor, Prototype Chaining, Combination Inheritance (the most popular of the lot), Prototypal, and others. It is up to the developer to decide which is easier. This approach is very simple

Q4.

Layla should take into account the variables and dependencies and also methods that are required by her custom object in javascript. Once listed with variables, Layla can move on to define methods that are functions that users can perform on list to ease their work. Like Sorting the list in their preferred order. Objects make it easy to traverse the list. She should take into notice how the implementation of list will go. Like variables can be CustomerName and GuitarType