What is remote scripting?
Remote scripting is a technology that allows us to call server side ASP script from the client using JavaScript. The main benefits of using remote scripting are that it's cross browser compatible (works on NS4.x+ and IE4.x+) and takes away the need to refresh a page when some sort of server action is required to either send/receive data.
The way in which remote scripting works is fairly trivial, and only requires a small amount of tinkering to get it up and running properly. Firstly, you must configure remote scripting on both the client and server (which we will look at next). Once it's configured, you create an ASP page containing all of the functions that you’d like to expose to the client and call them in a special way.
These functions are created is the same way that you would create any ASP functions (with the function myFunc()... end function syntax), however some server side JavaScript is also included with the ASP script allowing the client to view your entire ASP page as an object that exposes methods. The remote scripting engine handles all of this under the hood, so we don't need to go into detail about it here.
Installing remote scripting
The technology behind remote scripting is not extremely complicated, and to enable remote scripting capabilities on our IIS web server we only need a handful of files: rs.htm, rsproxy.class and rs.asp. These files are available for download as "Remote Scripting 1.0b" here, and you should download them before continuing.
When you run the setup program it will prompt you for an installation directory, which is C:\inetpub\wwwroot\_ScriptLibrary by default. When remote scripting is taking place, it assumes that it can find several files in the _ScriptLibrary folder on your IIS web server, so it's a good idea to change the c:\inetpub\wwwroot part of the installation path to match your default web directory. For example, if you currently store all of your files in c:\myweb and you’ve configured IIS to look in the c:\myweb folder when a HTTP request is received, then you should change the remote scripting installation path to c:\myweb\_ScriptLibrary.
Once you've installed remote scripting, you should see the following files and folders in the _ScriptLibrary folder under your IIS web folder:
- rs.htm: Contains the plumbing and functions that make remote scripting on the client side possible. Most notably, rs.htm contains three public methods called RSEnableRemoteScripting, RSExecute and RSGetASPObject. Rs.htm is implemented in JavaScript.
- rs.asp: Contains the plumbing and functions that make remote scripting on the server side possible. Its main method is RSDispatch, which handles all marshalling and the returning of data back to the client.
- rsproxy.class: A Java class that is dynamically added to the clients HTML output when rs.htm is called. It handles some of the internals that are required by the remote scripting engine to function correctly including the communication between the client and server scripts.
- /docs: Documentation detailing how to setup remote scripting, how to implement remote scripting into client and server code, etc.
- /samples: Contains a sample that implements remote scripting.