JScript
Encyclopedia
JScript is a scripting language based on the ECMAScript
standard that is used in Microsoft
's Internet Explorer
.
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 the Internet Explorer 3.0 browser released in August 1996. Its most recent version is JScript 9.0, included in Internet Explorer 9.
Another dialect of JScript (as of 2004 - 2006) was JScript .NET
, which was based on the yet-unfinished edition 4 of the ECMAScript standard, and can be compiled for the Microsoft .NET platform. JScript.NET, which added several new features to ECMAScript ed. 3, such as optional static type annotations, has been renamed Jscript 10.0.
in his talk entitled The JavaScript Programming Language on YUI Theater,
JScript supports conditional compilation, which allows a programmer to selectively execute code within block comments. This is an extension to the ECMAScript
standard that is not supported in other JavaScript implementations.
engine. Like other Active Scripting languages, it is built on the COM/OLE Automation
platform and provides scripting capabilities to host applications.
This is the version used when hosting JScript inside a Web page displayed by Internet Explorer
, in an HTML application, in classic ASP
, in Windows Script Host
scripts and several other Automation
environments.
JScript is sometimes referred to as "classic JScript" or "Active Scripting JScript" to differentiate it from newer .NET-based versions.
Some versions of JScript are available for multiple versions of Internet Explorer and Windows. For example, JScript 5.7 was introduced with Internet Explorer 7.0
and is also installed for Internet Explorer 6.0
with Windows XP
Service Pack 3, while JScript 5.8 was introduced with Internet Explorer 8.0
and is also installed with Internet Explorer 6.0 on Windows Mobile 6.5.
JScript is also available on Windows CE (included in Windows Mobile, optional in Windows Embedded CE). The Windows CE version lacks Active Debugging.
JScript .NET can be used for ASP.NET
pages and for complete .NET applications, but the lack of support for this language in Microsoft Visual Studio place it more as an upgrade path for classic ASP
using classic JScript than as a new first-class language.
JScript .NET is not supported in the .NET Compact Framework
.
Note: JScript .NET versions are not related to classic JScript versions. JScript .NET is a separate product. Even though JScript .NET is not supported within the Visual Studio IDE, its versions are in sync with other .NET languages versions (C#, VB.NET, VC++) that follows their corresponding Visual Studio versions.
.NET Framework 3.0 and 3.5 are built on top of 2.0 and do not include newer releases of JScript .NET.
(Source: file version of Microsoft.JScript.dll in each framework install)
ECMAScript
ECMAScript is the scripting language standardized by Ecma International in the ECMA-262 specification and ISO/IEC 16262. The language is widely used for client-side scripting on the web, in the form of several well-known dialects such as JavaScript, JScript, and ActionScript.- History :JavaScript...
standard that is used in Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
's Internet Explorer
Internet Explorer
Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...
.
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
Internet Explorer
Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...
, Active Server Pages
Active Server Pages
Active Server Pages , also known as Classic ASP or ASP Classic, was Microsoft's first server-side script engine for dynamically-generated Web pages. Initially released as an add-on to Internet Information Services via the Windows NT 4.0 Option Pack Active Server Pages (ASP), also known as Classic...
, and Windows Script Host
Windows Script Host
The Microsoft Windows Script Host is an automation technology for Microsoft Windows operating systems that provides scripting capabilities comparable to batch files, but with a greater range of supported features...
. It also means that any application supporting Windows Script can use multiple languages (JScript, VBScript
VBScript
VBScript is an Active Scripting language developed by Microsoft that is modeled on Visual Basic. It is designed as a “lightweight” language with a fast interpreter for use in a wide variety of Microsoft environments...
, Perl
Perl
Perl is a high-level, general-purpose, interpreted, dynamic programming language. Perl was originally developed by Larry Wall in 1987 as a general-purpose Unix scripting language to make report processing easier. Since then, it has undergone many changes and revisions and become widely popular...
, and others).
JScript was first supported in the Internet Explorer 3.0 browser released in August 1996. Its most recent version is JScript 9.0, included in Internet Explorer 9.
Another dialect of JScript (as of 2004 - 2006) was JScript .NET
JScript .NET
JScript .NET is a .NET programming language developed by Microsoft as a natural successor to Microsoft's Active Scripting language JScript, which, in turn, started life as an implementation of JavaScript....
, which was based on the yet-unfinished edition 4 of the ECMAScript standard, and can be compiled for the Microsoft .NET platform. JScript.NET, which added several new features to ECMAScript ed. 3, such as optional static type annotations, has been renamed Jscript 10.0.
Comparison to JavaScript
As explained by JavaScript guru Douglas CrockfordDouglas Crockford
Douglas Crockford is an American computer programmer and entrepreneur, best known for his ongoing involvement in the development of the JavaScript language, and for having popularized the data format JSON , and for developing JSLint...
in his talk entitled The JavaScript Programming Language on YUI Theater,
JScript supports conditional compilation, which allows a programmer to selectively execute code within block comments. This is an extension to the ECMAScript
ECMAScript
ECMAScript is the scripting language standardized by Ecma International in the ECMA-262 specification and ISO/IEC 16262. The language is widely used for client-side scripting on the web, in the form of several well-known dialects such as JavaScript, JScript, and ActionScript.- History :JavaScript...
standard that is not supported in other JavaScript implementations.
JScript
The original JScript is an Active ScriptingActive Scripting
Active Scripting is the technology used in Windows to implement component-based scripting support. It is based on COM and allows installation of additional scripting engines in the form of COM modules.-Uses and history:The Active Scripting technologies were first released in 1996, with the...
engine. Like other Active Scripting languages, it is built on the COM/OLE Automation
OLE Automation
In Microsoft Windows applications programming, OLE Automation , is an inter-process communication mechanism based on Component Object Model that was intended for use by scripting languages – originally Visual Basic – but now are used by languages run on Windows...
platform and provides scripting capabilities to host applications.
This is the version used when hosting JScript inside a Web page displayed by Internet Explorer
Internet Explorer
Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...
, in an HTML application, in classic ASP
Active Server Pages
Active Server Pages , also known as Classic ASP or ASP Classic, was Microsoft's first server-side script engine for dynamically-generated Web pages. Initially released as an add-on to Internet Information Services via the Windows NT 4.0 Option Pack Active Server Pages (ASP), also known as Classic...
, in Windows Script Host
Windows Script Host
The Microsoft Windows Script Host is an automation technology for Microsoft Windows operating systems that provides scripting capabilities comparable to batch files, but with a greater range of supported features...
scripts and several other Automation
OLE Automation
In Microsoft Windows applications programming, OLE Automation , is an inter-process communication mechanism based on Component Object Model that was intended for use by scripting languages – originally Visual Basic – but now are used by languages run on Windows...
environments.
JScript is sometimes referred to as "classic JScript" or "Active Scripting JScript" to differentiate it from newer .NET-based versions.
Some versions of JScript are available for multiple versions of Internet Explorer and Windows. For example, JScript 5.7 was introduced with Internet Explorer 7.0
Internet Explorer 7
Windows Internet Explorer 7 is a web browser released by Microsoft in October 2006. Internet Explorer 7 is part of a long line of versions of Internet Explorer and was the first major update to the browser in more than 5 years...
and is also installed for Internet Explorer 6.0
Internet Explorer 6
Internet Explorer 6 is the sixth major revision of Internet Explorer, a web browser developed by Microsoft for Windows operating systems...
with Windows XP
Windows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
Service Pack 3, while JScript 5.8 was introduced with Internet Explorer 8.0
Internet Explorer 8
Windows Internet Explorer 8 is a web browser developed by Microsoft in the Internet Explorer browser series. The browser was released on March 19, 2009 for Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, and Windows 7. Both 32-bit and 64-bit builds are available...
and is also installed with Internet Explorer 6.0 on Windows Mobile 6.5.
| Version | Date | Introduced with | Similar JavaScript JavaScript JavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles.... version |
|
|---|---|---|---|---|
| 1.0 | Aug 1996 | Internet Explorer 3.0 Internet Explorer 3 Microsoft Internet Explorer 3 is a graphical web browser released on August 13, 1996 by Microsoft for Microsoft Windows and on January 8, 1997 for Apple Mac OS . It began serious competition against Netscape Navigator in the first Browser war... |
Netscape JavaScript | 1.0 |
| 2.0 | Jan 1997 | Windows IIS Internet Information Services Internet Information Services – formerly called Internet Information Server – is a web server application and set of feature extension modules created by Microsoft for use with Microsoft Windows. It is the most used web server after Apache HTTP Server. IIS 7.5 supports HTTP, HTTPS,... 3.0 |
Netscape JavaScript | 1.1 |
| 3.0 | Oct 1997 | Internet Explorer 4.0 | ECMA-262 1st edition | 1.3 |
| 4.0 | Visual Studio Microsoft Visual Studio Microsoft Visual Studio is an integrated development environment from Microsoft. It is used to develop console and graphical user interface applications along with Windows Forms applications, web sites, web applications, and web services in both native code together with managed code for all... 6.0 (as part of Visual InterDev Visual InterDev Microsoft Visual InterDev, part of Microsoft Visual Studio 97 and 6.0, is an IDE used to create web applications using Microsoft Active Server Pages technologies. It has code completion, database server management tools, and an integrated debugger.... ) |
ECMA-262 1st edition | 1.3 | |
| 5.0 | Mar 1999 | Internet Explorer 5.0 | ECMA-262 2nd edition | 1.4 |
| 5.1 | Internet Explorer 5.01 | ECMA-262 2nd edition | 1.4 | |
| 5.5 | Jul 2000 | Internet Explorer 5.5 & Windows CE Windows CE Microsoft Windows CE is an operating system developed by Microsoft for embedded systems. Windows CE is a distinct operating system and kernel, rather than a trimmed-down version of desktop Windows... 4.2 |
ECMA-262 3rd edition | 1.5 |
| 5.6 | Oct 2001 | Internet Explorer 6.0 Internet Explorer 6 Internet Explorer 6 is the sixth major revision of Internet Explorer, a web browser developed by Microsoft for Windows operating systems... & Windows CE Windows CE Microsoft Windows CE is an operating system developed by Microsoft for embedded systems. Windows CE is a distinct operating system and kernel, rather than a trimmed-down version of desktop Windows... 5.0 |
ECMA-262 3rd edition | 1.5 |
| 5.7 | Nov 2006 | Internet Explorer 7.0 Internet Explorer 7 Windows Internet Explorer 7 is a web browser released by Microsoft in October 2006. Internet Explorer 7 is part of a long line of versions of Internet Explorer and was the first major update to the browser in more than 5 years... |
ECMA-262 3rd edition + ECMA-327 (ES-CP) | 1.5 |
| 5.8 | Mar 2009 | Internet Explorer 8.0 Internet Explorer 8 Windows Internet Explorer 8 is a web browser developed by Microsoft in the Internet Explorer browser series. The browser was released on March 19, 2009 for Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, and Windows 7. Both 32-bit and 64-bit builds are available... & Internet Explorer Mobile 6.0 |
ECMA-262 3rd edition + ECMA-327 (ES-CP) + JSON JSON JSON , or JavaScript Object Notation, is a lightweight text-based open standard designed for human-readable data interchange. It is derived from the JavaScript scripting language for representing simple data structures and associative arrays, called objects... (RFC 4627)3 |
1.5 |
| 9.0 | Mar 2011 | Internet Explorer 9.0 Internet Explorer 9 Windows Internet Explorer 9 is the current version of the Internet Explorer web browser from Microsoft. It was released to the public on March 14, 2011 at 21:00 PDT. Internet Explorer 9 supports several CSS 3 properties, embedded ICC v2 or v4 color profiles support via Windows Color System, and... |
ECMA-262 5th edition | 1.8.1 |
JScript is also available on Windows CE (included in Windows Mobile, optional in Windows Embedded CE). The Windows CE version lacks Active Debugging.
JScript .NET
JScript .NET is a Microsoft .NET implementation of JScript, it is a CLS language and thus inherits very powerful features, but lacks many features of the original JScript language, making it inappropriate for many scripting scenarios.JScript .NET can be used for ASP.NET
ASP.NET
ASP.NET is a Web application framework developed and marketed by Microsoft to allow programmers to build dynamic Web sites, Web applications and Web services. It was first released in January 2002 with version 1.0 of the .NET Framework, and is the successor to Microsoft's Active Server Pages ...
pages and for complete .NET applications, but the lack of support for this language in Microsoft Visual Studio place it more as an upgrade path for classic ASP
Active Server Pages
Active Server Pages , also known as Classic ASP or ASP Classic, was Microsoft's first server-side script engine for dynamically-generated Web pages. Initially released as an add-on to Internet Information Services via the Windows NT 4.0 Option Pack Active Server Pages (ASP), also known as Classic...
using classic JScript than as a new first-class language.
| Version | Platform | Date | Introduced with | Based on |
|---|---|---|---|---|
| 7.0 | Desktop CLR Common Language Runtime The Common Language Runtime is the virtual machine component of Microsoft's .NET framework and is responsible for managing the execution of .NET programs. In a process known as just-in-time compilation, the CLR compiles the intermediate language code known as CIL into the machine instructions... 1.0 |
2002-01-05 | Microsoft .NET Framework 1.0 | ECMA-262 3rd edition |
| 7.1 | Desktop CLR Common Language Runtime The Common Language Runtime is the virtual machine component of Microsoft's .NET framework and is responsible for managing the execution of .NET programs. In a process known as just-in-time compilation, the CLR compiles the intermediate language code known as CIL into the machine instructions... 1.1 |
2003-04-01 | Microsoft .NET Framework 1.1 | ECMA-262 3rd edition |
| 8.0 | Desktop CLR Common Language Runtime The Common Language Runtime is the virtual machine component of Microsoft's .NET framework and is responsible for managing the execution of .NET programs. In a process known as just-in-time compilation, the CLR compiles the intermediate language code known as CIL into the machine instructions... 2.0 |
2005-11-07 | Microsoft .NET Framework 2.0 | ECMA-262 3rd edition |
JScript .NET is not supported in the .NET Compact Framework
.NET Compact Framework
The Microsoft .NET Compact Framework is a version of the .NET Framework that is designed to run on resource constrained mobile/embedded devices such as personal digital assistants , mobile phones, factory controllers, set-top boxes, etc...
.
Note: JScript .NET versions are not related to classic JScript versions. JScript .NET is a separate product. Even though JScript .NET is not supported within the Visual Studio IDE, its versions are in sync with other .NET languages versions (C#, VB.NET, VC++) that follows their corresponding Visual Studio versions.
.NET Framework 3.0 and 3.5 are built on top of 2.0 and do not include newer releases of JScript .NET.
(Source: file version of Microsoft.JScript.dll in each framework install)
See also
- Active ScriptingActive ScriptingActive Scripting is the technology used in Windows to implement component-based scripting support. It is based on COM and allows installation of additional scripting engines in the form of COM modules.-Uses and history:The Active Scripting technologies were first released in 1996, with the...
- Chakra (JScript engine)Chakra (JScript engine)Chakra is a JScript engine developed by Microsoft for its Internet Explorer 9 web browser. A distinctive feature of the 32-bit version of the engine is that it JIT compiles scripts on a separate CPU core, parallel to the web browser...
- ECMAScriptECMAScriptECMAScript is the scripting language standardized by Ecma International in the ECMA-262 specification and ISO/IEC 16262. The language is widely used for client-side scripting on the web, in the form of several well-known dialects such as JavaScript, JScript, and ActionScript.- History :JavaScript...
, the ECMA InternationalEcma InternationalEcma International is an international, private non-profit standards organization for information and communication systems. It acquired its name in 1994, when the European Computer Manufacturers Association changed its name to reflect the organization's global reach and activities...
language definition standard which all implementations of this language family must at a minimum follow - JScript.NET
- JavaScriptJavaScriptJavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles....
, Originally LiveScript, it was the first implementation of this language family - Windows Script FileWindows Script FileA Windows Script File is a file type used by the Microsoft Windows Script Host. It allows mixing the scripting languages JScript and VBScript within a single file, or other scripting languages such as Perl, Object REXX, Python, or Kixtart if installed by the user...
- Windows Script HostWindows Script HostThe Microsoft Windows Script Host is an automation technology for Microsoft Windows operating systems that provides scripting capabilities comparable to batch files, but with a greater range of supported features...