Javascript example tutorial(20) OLE Automation(1)

Using OLE Automation in javaScript

　 In the previous tutorial, we have already mentioned OLE Automation in Javascript. In this tutorial, we will discuss how JavaScript uses the power of Automation to extend the capabilities of server-side scripts.

Actually Automation is not a new thing. It has been popular for several years, but support for the ActiveX scripting language is a new application. If you already have a programming background in Visual Basic or Visual C++, this tutorial will show you how to use your experience to create useful scripts to control external applications.

It is very powerful to control external applications in your script, such as opening a Word document or an Excel spreadsheet from your script. HTML editors such as HomeSite 4.0 and HotMetal PRo 6 provide you with a wealth of tools that you can leverage into your homepage. They are all encapsulated into ActiveX controls. The content of this tutorial mainly includes:

What is Automation

What is binding

How to create a new instance of an Automation object

How to retrieve an existing instance of an Automation object

How to handle instances of an application

How to improve scripts Program performance

How to deal with set objects

Starting from the next article, we will introduce the above content one by one.

Using OLE Automation in JavaScript

What is Automation

OLE (Object Connection and Embedding) Automation allows applications to communicate, exchange data, control other applications, and more. It also allows a client application to create and control an object by using an interface that exposes the object. An Automation object is an object that can be exposed to other applications or programming tools through the Automation interface.

Automation provides a documented, standard way to create and access applications. Usually, Automation is closely related to Visual Basic. It provides C/C++ developers with powerful tools for creating programmable applications and allows Visual Basic designers to access and manipulate these applications. These C/C++ programmers provide specialized user interface solutions and give Visual Basic programmers a reliable way to assemble custom solutions from application components.

Not only Visual Basic can take advantage of Automation, in fact, programmable objects can also be accessed by any macro language or programming tool that executes Automation. Users can choose a programming tool based on their current knowledge rather than learning a new language for each application. Even scripting languages ​​such as VBScript and Jscript pages support Automation.

The key to controlling an Automation application is to have a good understanding of the application's object model. Every application's object model is different. Microsoft now claims that every function of every application in the Office program group can be accessed by programmers through the application's object model. This Office suite of programs exposes thousands of objects, methods, and properties to programmers through its object model. This news is undoubtedly good news for programmers.

However, learning the object model of a particular application is often difficult because of the lack of documentation describing the various software objects. Microsoft Office applications, for example, provide programmers with extensive documentation online, but there are many other applications that do not provide the necessary documentation.

The object browser in Microsoft Visaul Basic displays objects, methods, properties, and constants of external Automation objects in a dialog box. This tool is also useful in scripting, since application global constants are not valid in a scripting environment. If you use Automation to write scripts, you can use the Object Browser to retrieve the values ​​of the necessary constants so that you can explicitly specify them in the script.

The above is the content of Javascript example tutorial (20) OLE Automation (1). For more related content, please pay attention to the PHP Chinese website (www.php.cn)!