TAILIEUCHUNG - JavaScript Bible, Gold Edition part 20

JavaScript Bible, Gold Edition part 20. This book will bring programmers and non-technical professionals, including casual programmers and scripters, painlessly up to speed on all aspects of mastering JavaScript. Key topics include programming fundamentals, JavaScript language elements and how to use them effectively, and how to easily and efficiently add powerful new functionality to HTML documents and Java applets. | 38 Part III Document Objects Reference property for any generated array. Later in this chapter you see how to direct a browser to use a specific version of JavaScript for script execution if that makes sense to your application. In practice however the JavaScript version implemented in a browser is not always a good predictor of core language features available for that browser. For example while JavaScript as implemented by Netscape in NN4 includes broad support for regular expressions not all of those features appear in Microsoft s JavaScript implementation in IE4. By the same token Microsoft implemented try-catch error handling in its version of JavaScript in IE5 but Netscape didn t include that feature until its NN6 implementation of JavaScript . Therefore the language version number is far less important than the browser version in determining which language features to use. Core Language Standard-ECMAScript Although Netscape first developed the JavaScript language Microsoft incorporated the language in Internet Explorer 3. Because Microsoft did not want to license the Java name from its trademark owner Sun Microsystems the language became known in the IE environment as JScript. Except for some very esoteric exceptions and the pace of newly introduced features the two languages are essentially identical. The levels of compatibility between browser brands for a comparable generation are remarkably high for the core language unlike the vast disparities in object model implementations discussed in Chapter 14 . As mentioned in Chapter 2 standards efforts have been under way to create industry-wide recommendations for browser makers to follow to make developers lives easier . The core language was among the first components to achieve standard status. Through the European standards body called ECMA a formal standard for the language has been agreed to and published. The first specification for the language dubbed ECMAScript by the standards group was

TỪ KHÓA LIÊN QUAN
TAILIEUCHUNG - Chia sẻ tài liệu không giới hạn
Địa chỉ : 444 Hoang Hoa Tham, Hanoi, Viet Nam
Website : tailieuchung.com
Email : tailieuchung20@gmail.com
Tailieuchung.com là thư viện tài liệu trực tuyến, nơi chia sẽ trao đổi hàng triệu tài liệu như luận văn đồ án, sách, giáo trình, đề thi.
Chúng tôi không chịu trách nhiệm liên quan đến các vấn đề bản quyền nội dung tài liệu được thành viên tự nguyện đăng tải lên, nếu phát hiện thấy tài liệu xấu hoặc tài liệu có bản quyền xin hãy email cho chúng tôi.
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.