View source for Language - Visual Basic Script

[[Category:Language]]
{{OSLang|[[File:icon-Visual Basic Script.png|64x64px|alt=|link=]]|'''VBScript''' ('''V'''isual '''B'''asic '''Script'''ing Edition) is an [http://en.wikipedia.org/wiki/Active_Scripting Active Scripting] language developed by [http://msdn.microsoft.com/en-us/library/t0aew7h6 Microsoft] that is modeled on [[Language_-_Visual_Basic_6.0|Visual Basic]].}}
__TOC__

==Introduction==

{{LanguageSupport|VBScript|the complete Phidget API, including events|Encoder, InterfaceKit and RFID.|various script editors, although the programs themselves only run in Internet Explore (IE)|}}

==Quick Downloads==
{{QuickDownloads|VBScript|
{{APIQuickDownloads|http://www.phidgets.com/documentation/COM_API_Manual.pdf .COM}}|
{{ExampleQuickDownloads|http://www.phidgets.com/downloads/examples/VBScript.zip|}}|
{{WindowsQuickDownloads}}}}

==Getting started with VBScript==

If you are new to writing code for Phidgets, we recommend starting by running, then modifying existing examples. This will allow you to:
{{ExampleCodeReasons}}

Visual Basic script is only supported under [[#Windows(2000/XP/Vista/7)|Windows 2000 / XP / Vista / 7]], and then for use only under Internet Explorer.

==Windows (2000/XP/Vista/7)==

===Use Our Examples===

===Write Your Own Code===

To begin, load the HTML editor of your choice and create a new document. 
Add a table to body of the code for the purpose of displaying simple output.

<div class="source"><syntaxhighlight lang=html4strict>
 
  <html>
  <head> 
  <body>
  <form action=”html_interfacekit.htm”>
  <table id=”mytable”>
       <thead>
     <tr><td>Analog Input</td></tr>
       </thead>
  <tr id=”tr0”><td>0</td> </tr>
  <tr id=”tr1”><td>0</td> </tr>
  <tr id=”tr2”><td>0</td> </tr>
  <tr id=”tr3”><td>0</td> </tr>
  <tr id=”tr4”><td>0</td> </tr>
  <tr id=”tr5”><td>0</td> </tr>
  <tr id=”tr6”><td>0</td> </tr>
  <tr id=”tr7”><td>0</td> </tr>
  </table>
  </form>
  </body>
  </html>
 
</syntaxhighlight></div>

Before you can use the Phidget, you must include its Class ID on object creation in your code. 
This will let the browser know which library to try and load for the Phidget definitions. 
Each type of Phidget has its ClassID listed inside the ClassID_List.txt document from the VBScript examples. 
For example, we can declare and create a PhidgetInterfaceKit for vbscript with:

<div class="source"><syntaxhighlight lang=html4strict>
 
  <object classid="clsid:50484945-4745-5453-3000-000000000003" id="phid"></object>
  <script type="text/vbscript">
     <!--Your Code goes here-->
  </script>
 
</syntaxhighlight></div>

The object name for any type of Phidget is listed in the API manual. 
Every type of Phidget also inherits functionality from the Phidget base class.


==Follow The Examples==


===Code Snippets===

====Step One: Initialize and Open====

The program can try to connect to the Phidget through an open call. 
Open will continuously try to connect to a Phidget, based on the parameters given, even trying to reconnect if it gets disconnected. 
This means that simply calling open does not guarantee you can use the Phidget immediately. 
We can account for a connection by using event driven programming and tracking the AttachEvents and DetachEvents, or by calling WaitForAttachment. 
WaitForAttachment will block indefinitely until a connection is made to the Phidget, or an optional timeout is exceeded.

<div class="source"><syntaxhighlight lang=vb>
 
  phid.Open()
  phid.WaitForAttachment (3000)
 
</syntaxhighlight></div>

The different parameters and open calls can be used to open the first Phidget of a type it can find, open based on a serial number, or even open across the network. 
The API manual lists all of the available modes that open provides.
One important thing to remember is that when working with Phidgets, a local connection will reserve the device until closed. 
This prevents any other instances from retrieving data from the Phidget, including other programs. 
The one connection per device limit does not apply when exclusively using the Phidget Webservice.

====Step Two: Wait for Attachment (plugging in) of the Phidget====

====Step Three: Do Things with the Phidget====

We recommend the use of event driven programming when working with Phidgets. 
In VBScript, we hook an event handler with the following code:

<div class="source"><syntaxhighlight lang=vb>
  
  Sub phid_OnSensorChange(ByVal Index, ByVal SensorValue)
     mytable.rows("str"+CStr(Index)).cells(0).innerText = Cstr(InterfaceKit1.sensorValue(Index))
  End Sub
 
</syntaxhighlight></div>

With this method, the code inside onSensorChange will get executed every time the PhidgetInterfaceKit reports a change on one of its analog inputs. 

Some events such as Attach and Detach belong to the base Phidget object and thus are common to all types of Phidgets. 
Please refer to the API manual for a full list of events and their usage.

Some values can be directly read and set on the Phidget, and inside polling loops used as an alternative to event driven programming. 
Simply use the instance properties such as phid.SensorChangeTrigger(Index) for PhidgetInterfaceKits.

<div class="source"><syntaxhighlight lang=vb>

  phid.SensorChangeTrigger(0) = 1

</syntaxhighlight></div>

====Step Four: Close and Delete====

{{MoreHowTos}}

==Common Problems and Solutions/Workarounds==

None at this time.