JScript
From Wikipedia, the free encyclopedia
JScript is a computer programming language created by Microsoft and is a superset of the ECMAScript programming language.
JScript is implemented as a Windows Script engine. This means that it can be "plugged in" to any application that supports Windows Script, such as Internet Explorer, Active Server Pages, and Windows Script Host. It also means that any application supporting Windows Script can use multiple languages — JScript, VBScript, Perl, and others. JScript was first supported in Internet Explorer browser 3.0 released in August 1996. As with any other Active Scripting engine, it is available through Internet Explorer, Windows Script Host, and Active Server Pages. The typical file extension of JScript source code files is .js.
The most recent version of JScript is JScript .NET, which is based on the yet-unfinished version 4 of the ECMAScript standard, and can be compiled for the Microsoft .NET platform. JScript adds several new features to ECMAScript, such as optional static type annotations.
In addition to other internal implementation differences, JScript uses non-generational mark-and-sweep garbage collection[1] whereas JavaScript (the original implementation of which is the SpiderMonkey engine) uses a generational mark-and-sweep system.
JScript can be used for both simple tasks (such as mouseovers on Web pages) and for more complex tasks (such as updating a database with ASP or running logon scripts for Windows NT ). Windows Script relies on external "object models" to carry out much of its work. For example, Internet Explorer's DOM provides objects such as 'document' and methods such as 'write()' to enable the scripting of Web pages.
[edit] Versions
| Version | Date | Introduced with | Approx. JavaScript |
|---|---|---|---|
| 1.0 | Aug 1996 | IE 3.0 | 1.0 |
| 2.0 | Jan 1997 | IIS 3.0 | 1.1 |
| 3.0 | Oct 1997 | IE 4.0 | 1.3 |
| 4.0 | VS 6.0 | ||
| 5.0 | Mar 1999 | IE 5.0 | 1.5 |
| 5.1 | IE 5.01 | 1.5 | |
| 5.5 | Jul 2000 | IE 5.5 | 1.5 |
| 5.6 | Oct 2001 | IE 6.0 | 1.5 |
| 5.7 | Nov 2006 | Windows Vista | 1.5 |
| .NET | 2000-7-11 | Microsoft .NET Framework 1.0 | ? |
| 8.0 | ? | ? | ? |
(Source: MSDN, WebmasterWorld Forum)
[edit] See also
- Hello World program in JScript
- JavaScript, the first ECMAScript implementation which also helped to evolve the ECMAScript standard
- ECMAScript, the ECMA language definition standard which all implementations must at a minimum follow
- VBScript
