Introduction to Unobtrusive Javascript
Unobtrusive JavaScript is an approach to the use of JavaScript in web pages to achieve its basic principles as below: • Separation of functionality (the “behavior layer”) from a Web page’s structure/content and presentation. • Best practices to avoid the problems of traditional JavaScript programming (such as browser inconsistencies and lack of scalability) • Progressive enhancement to support user agents that may not support advanced JavaScript functionality. Separation of behavior from markup Traditionally Javascript is fed into inline HTML document markup as a functions or query. Lets consider typical implementation of JS form validation when placed inline: <input type=" text " name=" date " onchange=" validateDate() " /> Adherents of “Unobtrusive JavaScript” contend that purpose of markup is to describe a documents structure, not its programmatic behavior .Also the inline event handlers are harder to use and maintain, when one needs to set handl