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JavaScript Bible, Gold Edition part 53

JavaScript Bible, Gold Edition part 53. 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. | 368 Part III Document Objects Reference Table 18-3 NN6 document.implementation.hasFeature Support Feature Versions XML 1.0 2.0 HTML 1.0 2.0 Views 2.0 StyleSheets 2.0 CSS 2.0 Events 2.0 MouseEvents 2.0 HTMLEvents 2.0 Range 2.0 On the Example on the CD CD-ROM r lastModified Value Date String Read-Only NN2 NN3 NN4 NN6 IE3 J1 IE3 J2 IE4 IE5 IE5.5 Compatibility Every disk file maintains a modified timestamp and most but not all servers are configured to expose this information to a browser accessing a file. This information is available by reading the document.lastModified property. If your server supplies this information to the client you can use the value of this property to present this information for readers of your Web page. The script automatically updates the value for you rather than requiring you to hand-code the HTML line every time you modify the home page. If the value returned to you displays itself as a date in 1969 it means that you are positioned somewhere west of GMT or Greenwich Mean Time some number of time zones west of GMT at 1 January 1970 and the server is not providing the proper data when it serves the file. Sometimes server configuration can fix the problem but not always. The returned value is not a date object Chapter 36 but rather a straight string consisting of time and date as recorded by the document s file system. The format of the string varies from browser to browser and version to version. You can however usually convert the date string to a JavaScript date object and use the date document.lastModified Chapter 18 The Document and Body Objects 369 object s methods to extract selected elements for recompilation into readable form. Listing 18-6 shows an example. Some browser versions running in Windows 95 may return a two-digit year which Note will lead to Y2K problems when generating a date object. Even local file systems don t necessarily provide the correct data for every browser to interpret. For example in Navigator of all .