Language - Visual Basic: Difference between revisions

From Phidgets Support
No edit summary
 
(121 intermediate revisions by 9 users not shown)
Line 1: Line 1:
Preamble about the language and its general strengths and weaknesses.
{{#seo:|description=Learn how to use Phidget USB devices with Visual Basic.}}
[[Category:Language]]


==Assessment for use with Phidgets==
==Get Started==
Our honest opinion on how well this language is suited to controlling Phidgets. If it is a poor choice, suggest and link similar (better) languages.
With the Phidget22.NET library, it's easy to create VB applications that work with Phidget devices.


==Support==
==VB Libraries==
Visual Basic .NET has a complete API and sample code for all Phidgets devices.
===Nuget Package===
The Phidget22.NET library is available as a [https://www.nuget.org/packages/Phidget22.NET/ nuget package]. This is the recommend way to install and manage the Phidget22.NET library.


For a complete list of our supported languages and their support status, [[Levels of Support|click here]].
===Library Files===
If you would like to manually manage the Phidget22.NET library files, you can download them [https://cdn.phidgets.com/downloads/phidget22/libraries/windows/Phidget22-windevel.zip here].


==Restrictions==
==Development Environment Configuration==
In this section, list any restrictions or limitations that this particular language may impose. For example, incompatibility with certain operating systems.
===Visual Studio===
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
|+ '''Instructions'''
| {{hiddenh4|Start with the Code Samples}} ||
|-
| One of the best ways to start programming with Phidgets is to use our [https://www.phidgets.com/?view=code_samples&lang=VBNET example code] as a guide. Download the example(s) that correspond to your Phidget's channel classes. You can find them listed on the enclosure in most cases, or on the API tab of the product page. || [[Image:Language_vb_sample.jpg|center|350px|link=https://cdn.phidgets.com/docs/images/4/42/Language_vb_sample.jpg]]
|-
| Unpack and open the example project and click the Start button. The application will open the Phidget, list basic information about the Phidget, and demonstrate the Phidget's functionality.  || [[Image:Language_vb_start.png|center|350px|link=https://cdn.phidgets.com/docs/images/b/ba/Language_vb_start.png]]
|-
| {{hiddenh4|Editing the Examples}} ||
|-
| The Visual Basic .Net examples are derived from the Windows [[Phidget Control Panel]], so you'll need to modify a few things to adapt them for your own purposes. To begin with, you can remove the following line: ||
|-
|colspan="2"| <syntaxhighlight lang=vbnet>commandLineData phidgetParameters = open.parseCmdLine(); //get command line parameters</syntaxhighlight> ||
|-
|colspan="2"| Then, you can modify any line that mentions phidgetParameters by setting it to the desired value instead of using PhidgetParameters object. ||
|-
|colspan="2"| For instance:<syntaxhighlight lang=vbnet>Try 'set all the values grabbed from command line.  these values have defaults that are set in ExampleUtils.vb, you can check there to see them
    device.Channel = phidgetParameters.Channel 'selects the channel on the device to open
    device.DeviceSerialNumber = phidgetParameters.SerialNumber 'selects the device or hub to open
    device.HubPort = phidgetParameters.HubPort 'selects th eport on the hub to open
    device.IsHubPortDevice = phidgetParameters.isHubPortDevice 'is the device a port on a vint hub?


==Development Environments and Compilers==
    If phidgetParameters.isRemote Then 'are we trying to open a remote device?
        device.IsRemote = True
        Net.EnableServerDiscovery(ServerType.Device) 'turn on network scan
        If phidgetParameters.Password <> vbNullString And
          phidgetParameters.ServerName <> vbNullString Then
         
            Net.SetServerPassword(phidgetParameters.ServerName, phidgetParameters.Password)
        End If
    Else
        device.IsLocal = True
    End If


Describe each major compiler and notable differences or important information. (eg. framework versions) If there are known issues/workarounds mention them and link to the corresponding issue at the bottom of the page.  
    device.Open() 'open the device specified by the above parameters
Catch ex As PhidgetException
    errorBox.addMessage("Error opening the device: " + ex.Message)
End Try</syntaxhighlight>
|-
|colspan="2"|  Might become: <syntaxhighlight lang=vbnet> Try
    device.Channel = 0
    device.DeviceSerialNumber = 370097
    device.HubPort = 0
    device.IsHubPortDevice = True
    device.IsLocal = True


==Quick Downloads==
    device.Open()
Before you can run your program, you need to set up the proper environment and get the necessary files off the Phidgets website.  
Catch ex As PhidgetException
Visit the drivers section at www.phidgets.com and get the latest:
    errorBox.addMessage("Error opening the device: " + ex.Message)
* [http://www.phidgets.com/drivers.php Phidget Framework]
End Try</syntaxhighlight> You can then manipulate the rest of the code as your application requires.
You will need the Phidget Framework to use and to program with Phidgets. We also recommend that you download the following reference materials:
|-
* [http://www.phidgets.com/documentation/Phidget21.NET.zip API Manual]
| {{hiddenh4|Setting up a New Project}} ||
* [http://www.phidgets.com/documentation/web/NETDoc/Index.html API Reference]
|-
* [http://www.phidgets.com/downloads/examples/VBNET_2.1.8.20110616.zip VB.NET Sample Code]
| When you are building a project from scratch, or adding Phidget functionality to an existing project, you'll need to configure your development environment to properly link the Phidget .NET library. Create a new VB Forms Application, open the NuGet package manager. || [[Image:Language_vb_nuget.png|center|350px|link=https://cdn.phidgets.com/docs/images/4/4e/Language_vb_nuget.png]]
* You can find a high level discussion about programming with Phidgets in general on the [[General API]] page.  
|-
* The [[Device Functionality]] page explains the general operational information for your device.
| On the following screen, click '''Browse''', search for Phidget22, and install the Phidget22.NET package. || [[Image:Language_vb_nuget_install.png|center|350px|link=https://cdn.phidgets.com/docs/images/7/74/Language_vb_nuget_install.png]]
|-
|colspan="2"| Then, you just need to add the following lines: <syntaxhighlight lang=vbnet>Imports Phidget22
Imports Phidget22.Events</syntaxhighlight> The project now has access to Phidgets.
|}


You may want to have these pages open while working through these instructions.
===Mono===
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
|+ '''Instructions'''
| {{hiddenh4|HelloWorld Example}} ||
|-
|colspan="2"|First, download and unpack the [https://www.phidgets.com/downloads/phidget22/examples/dotnet/csharp/Manager/Phidget22_HelloWorld_CSharp_Windows_Ex.zip HelloWorld example] for VB. This example uses the [[Phidget Manager]] to list all Phidget channels that can be accessed by your computer. All other VB examples use Windows Forms, so they are not compatible with Mono.
|-
|Next, copy Phidget22.NET.dll from type the following location:<syntaxhighlight>C:\Program Files\Phidgets\Phidget22\Phidget22.NET.dll</syntaxhighlight>Place both the HelloWorld example and the Phidget22.NET.dll file in the same location. || [[Image:Language_vb_dll_folder.png|center|350px|link=https://cdn.phidgets.com/docs/images/8/89/Language_vb_dll_folder.png]]
|-
|colspan="2"|Open the command prompt at the folder location and enter the following command:<syntaxhighlight>vbnc /r:Phidget22.NET.dll Module1.vb</syntaxhighlight>This will create an executable file called Module1.exe. Type in the following command to run the example:<syntaxhighlight>mono Module1.exe</syntaxhighlight>
|-
|You should be able to see the channels of your Phidget listed when the program starts or whenever the Phidget is plugged in while the program is running.<br/><br/>Now that you've confirmed that your devices are properly connected, the next step is to download and edit sample code for your specific device.  || [[Image:Language_vb_console.png|center|350px|link=https://cdn.phidgets.com/docs/images/5/5e/Language_vb_console.png]]
|-
| {{hiddenh4|Other Examples}} ||
|-
| To download the code samples, visit [https://www.phidgets.com/?view=code_samples&lang=VBNET this page].  Download the example(s) that correspond to your Phidget's channel classes. You can find them listed on the enclosure in most cases, or on the API tab of the product page. || [[Image:Language_vb_sample.jpg|center|350px|link=https://cdn.phidgets.com/docs/images/4/42/Language_vb_sample.jpg]]
|-
|colspan="2"|The Visual Basic examples are derived from the Windows Phidget Control Panel, so you'll need to modify a few things to adapt them for your own purposes. To begin with, you can remove the following line:
<syntaxhighlight lang=vbnet>commandLineData phidgetParameters = open.parseCmdLine(); //get command line parameters</syntaxhighlight>Then, you can modify any line that mentions '''phidgetParameters''' by setting it to the desired value instead of using PhidgetParameters object.
|-
|colspan="2"| For instance:<syntaxhighlight lang=vbnet>Try 'set all the values grabbed from command line.  these values have defaults that are set in ExampleUtils.vb, you can check there to see them
    device.Channel = phidgetParameters.Channel 'selects the channel on the device to open
    device.DeviceSerialNumber = phidgetParameters.SerialNumber 'selects the device or hub to open
    device.HubPort = phidgetParameters.HubPort 'selects th eport on the hub to open
    device.IsHubPortDevice = phidgetParameters.isHubPortDevice 'is the device a port on a vint hub?


==Getting Started==
    If phidgetParameters.isRemote Then 'are we trying to open a remote device?
        device.IsRemote = True
        Net.EnableServerDiscovery(ServerType.Device) 'turn on network scan
        If phidgetParameters.Password <> vbNullString And
          phidgetParameters.ServerName <> vbNullString Then
         
            Net.SetServerPassword(phidgetParameters.ServerName, phidgetParameters.Password)
        End If
    Else
        device.IsLocal = True
    End If


The Phidget examples were written using Visual Basic .NET 2005 and this tutorial assumes its use.  
    device.Open() 'open the device specified by the above parameters
Newer versions of Visual Studio Express are freely available for download from Microsoft.  
Catch ex As PhidgetException
Older versions of Visual Studio work as well and would be set up in a similar manner (Note: you would have to recreate the user interface in the examples for Visual Studio versions earlier than 2005).  
    errorBox.addMessage("Error opening the device: " + ex.Message)
End Try</syntaxhighlight>
|-
|colspan="2"|  Might become: <syntaxhighlight lang=vbnet> Try
    device.Channel = 0
    device.DeviceSerialNumber = 370097
    device.HubPort = 0
    device.IsHubPortDevice = True
    device.IsLocal = True


In Visual Studio:
    device.Open()
Catch ex As PhidgetException
    errorBox.addMessage("Error opening the device: " + ex.Message)
End Try</syntaxhighlight> You can then manipulate the rest of the code as your application requires.
|-
| {{hiddenh4|Setting up a New Project}} ||
|-
|colspan="2"| To start a project from scratch, or add Phidget functionality to an existing project, you'll need to include the Phidget .NET library by adding the following lines to your code:<syntaxhighlight lang=vbnet>Imports Phidget22
Imports Phidget22.Events</syntaxhighlight>
|-
| Next, copy Phidget22.NET.dll from the following location:<syntaxhighlight>C:\Program Files\Phidgets\Phidget22\Phidget22.NET.dll</syntaxhighlight> Place your program and the Phidget22.NET.dll file in the same location. || [[Image:Language_vb_dll_folder.png|center|350px|link=https://cdn.phidgets.com/docs/images/8/89/Language_vb_dll_folder.png]]
|-
| Open the command prompt at the folder location and enter the following command:<syntaxhighlight>vbnc /r:Phidget22.NET.dll Module1.vb</syntaxhighlight>This will create an executable file called '''Module1.exe'''. Type in the following command to run the example:<syntaxhighlight>mono Module1.exe</syntaxhighlight>The project now has access to Phidgets.
|}


* Generate a new VB.NET Windows Application with a descriptive name such as PhidgetTest.
==Example Code==
* Launch the Add Reference window (Project | Add Reference).
Navigate to our [https://www.phidgets.com/?view=code_samples&lang=VBNET Code Samples Page] to view and download code samples that are tailored to your specific device. These code samples all use Windows Forms, except for the "Hello World" manager example.  
* Under the .NET tab, select the most recent Phidget21.NET library. If it does not appear in this list, then you can Browse to the Phidget Framework installation directory and add the Phidget21.NET.dll. For earlier versions of Visual Studio, you will want to use the Phidget21.NET1.1.dll instead.
* Place a TextBox on your main form for the purpose of capturing output.
* Hook the form's Load and FormClosing events. Phidget initialization and shutdown will take place there.  


The project now has access to Phidgets and we are ready to begin coding.
===Phidget Programming Basics===
{{PhidgetProgrammingBasicsLink}}


===Coding For Your Phidget===
==API==
 
[{{SERVER}}/?view=api&lang=CSharp Phidget22 API]
A Phidget object will fist need to be declared and then initialized. For example, we can declare a PhidgetInterfaceKit inside our form with:
 
<div style="background-color: #f3f3f3; border-color: #1c9edb; border-width:1px; border-style: dashed;">
<font size="3">
<source lang=vbnet>
 
  Public Class Form1
      'The Phidget object declaration
  Dim WithEvents ifKit As Phidgets.InterfaceKit
      '... Form1_Load and Form1_OnClosing here
  End Class
 
</source>
</font>
</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.
 
===Connecting to the Phidget===
 
Next, the program needs to try and connect to the Phidget through a call to open().
Open will tell the program to 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 immediately use the Phidget.
We can handle this 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 style="background-color: #f3f3f3; border-color: #1c9edb; border-width:1px; border-style: dashed;">
<font size="3">
<source lang=vbnet>
     
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        ifKit = New Phidgets.InterfaceKit
        ifKit.open()
        ifKit.waitForAttachment(3000)
    End Sub
 
</source>
</font>
</div>
 
The different types of open can be used with parameters to try and get the first device it can find, open based on its 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.
 
===Event Driven Programming===
 
We recommend the use of event driven programming when working with Phidgets.
In VB.NET we can hook an event handler with the following code:
<div style="background-color: #f3f3f3; border-color: #1c9edb; border-width:1px; border-style: dashed;">
<font size="3">
<source lang=vbnet>
 
    Private Sub ifKit_SensorChange(ByVal sender As Object, ByVal e As Phidgets.Events.SensorChangeEventArgs) Handles ifKit.SensorChange
        TextBox1.Text = "Index " + e.Index.ToString() + " Value: " + e.Value.ToString()
    End Sub
 
</source>
</font>
</div>
 
With this function, the code inside ifKit_SensorChange 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.
At the end of your program, unhook any events and call Application.DoEvents().
This will make sure there are no outstanding events being processed before calling close.
 
<div style="background-color: #f3f3f3; border-color: #1c9edb; border-width:1px; border-style: dashed;">
<font size="3">
<source lang=vbnet>
 
    Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        RemoveHandler ifKit.SensorChange, AddressOf ifKit_SensorChange
        Application.DoEvents()
        ifKit.close()
    End Sub
 
</source>
</font>
</div>
 
===Working directly with the Phidget===
 
Some values can be read and sent directly to the Phidget, simply use the instance members and properties.
This is also how you would set properties on the Phidget such as the output state or sensor sensitivity.
These functions can be used inside a polling loop as an alternative to event driven programming.
 
<div style="background-color: #f3f3f3; border-color: #1c9edb; border-width:1px; border-style: dashed;">
<font size="3">
<source lang=vbnet>
 
  Dim val As Integer = ifKit.sensors(0).Value
 
</source>
</font>
</div>
 
===Working with multiple Phidgets===
 
Multiple Phidgets of the same type can easily be run inside the same program.
In our case, it requires another PhidgetInterfaceKit instance to be defined and initialized.
The new instance can then be set up, opened and used in the same process as the previous one.
If the application needs to distinguish between the devices, open can be called with the serial number of a specific Phidget.
 
===Other Phidgets===
 
The design given in this document can also be followed for almost all Phidgets.
For example, if you were using a PhidgetRFID instead of an PhidgetInterfacekit, you would declare an RFID object instead of an InterfaceKit.
The methods and events available would change but they can be accessed in a similar manner.
 
==Building your Project==
Describe the different ways a project could be built using this language.
 
==Common Problems and Solutions/Workarounds==
Here you can put various frequent problems and our recommended solutions.

Latest revision as of 21:25, 13 March 2026


Get Started

With the Phidget22.NET library, it's easy to create VB applications that work with Phidget devices.

VB Libraries

Nuget Package

The Phidget22.NET library is available as a nuget package. This is the recommend way to install and manage the Phidget22.NET library.

Library Files

If you would like to manually manage the Phidget22.NET library files, you can download them here.

Development Environment Configuration

Visual Studio

Instructions
Start with the Code Samples
One of the best ways to start programming with Phidgets is to use our example code as a guide. Download the example(s) that correspond to your Phidget's channel classes. You can find them listed on the enclosure in most cases, or on the API tab of the product page.
Language vb sample.jpg
Unpack and open the example project and click the Start button. The application will open the Phidget, list basic information about the Phidget, and demonstrate the Phidget's functionality.
Language vb start.png
Editing the Examples
The Visual Basic .Net examples are derived from the Windows Phidget Control Panel, so you'll need to modify a few things to adapt them for your own purposes. To begin with, you can remove the following line: 
commandLineData phidgetParameters = open.parseCmdLine(); //get command line parameters
Then, you can modify any line that mentions phidgetParameters by setting it to the desired value instead of using PhidgetParameters object.
For instance:
Try 'set all the values grabbed from command line.  these values have defaults that are set in ExampleUtils.vb, you can check there to see them
    device.Channel = phidgetParameters.Channel 'selects the channel on the device to open
    device.DeviceSerialNumber = phidgetParameters.SerialNumber 'selects the device or hub to open
    device.HubPort = phidgetParameters.HubPort 'selects th eport on the hub to open
    device.IsHubPortDevice = phidgetParameters.isHubPortDevice 'is the device a port on a vint hub?

    If phidgetParameters.isRemote Then 'are we trying to open a remote device?
        device.IsRemote = True
        Net.EnableServerDiscovery(ServerType.Device) 'turn on network scan
        If phidgetParameters.Password <> vbNullString And 
           phidgetParameters.ServerName <> vbNullString Then
           
            Net.SetServerPassword(phidgetParameters.ServerName, phidgetParameters.Password)
        End If
    Else
        device.IsLocal = True
    End If

    device.Open() 'open the device specified by the above parameters
Catch ex As PhidgetException
    errorBox.addMessage("Error opening the device: " + ex.Message)
End Try
Might become: 
 Try
    device.Channel = 0
    device.DeviceSerialNumber = 370097
    device.HubPort = 0
    device.IsHubPortDevice = True
    device.IsLocal = True

    device.Open()
Catch ex As PhidgetException
    errorBox.addMessage("Error opening the device: " + ex.Message)
End Try
You can then manipulate the rest of the code as your application requires.
Setting up a New Project
When you are building a project from scratch, or adding Phidget functionality to an existing project, you'll need to configure your development environment to properly link the Phidget .NET library. Create a new VB Forms Application, open the NuGet package manager.
Language vb nuget.png
On the following screen, click Browse, search for Phidget22, and install the Phidget22.NET package.
Language vb nuget install.png
Then, you just need to add the following lines: 
Imports Phidget22
Imports Phidget22.Events
The project now has access to Phidgets.

Mono

Instructions
HelloWorld Example
First, download and unpack the HelloWorld example for VB. This example uses the Phidget Manager to list all Phidget channels that can be accessed by your computer. All other VB examples use Windows Forms, so they are not compatible with Mono.
Next, copy Phidget22.NET.dll from type the following location:
C:\Program Files\Phidgets\Phidget22\Phidget22.NET.dll
Place both the HelloWorld example and the Phidget22.NET.dll file in the same location.
Language vb dll folder.png
Open the command prompt at the folder location and enter the following command:
vbnc /r:Phidget22.NET.dll Module1.vb
This will create an executable file called Module1.exe. Type in the following command to run the example:
mono Module1.exe
You should be able to see the channels of your Phidget listed when the program starts or whenever the Phidget is plugged in while the program is running.

Now that you've confirmed that your devices are properly connected, the next step is to download and edit sample code for your specific device.
Language vb console.png
Other Examples
To download the code samples, visit this page. Download the example(s) that correspond to your Phidget's channel classes. You can find them listed on the enclosure in most cases, or on the API tab of the product page.
Language vb sample.jpg
The Visual Basic examples are derived from the Windows Phidget Control Panel, so you'll need to modify a few things to adapt them for your own purposes. To begin with, you can remove the following line: 
commandLineData phidgetParameters = open.parseCmdLine(); //get command line parameters
Then, you can modify any line that mentions phidgetParameters by setting it to the desired value instead of using PhidgetParameters object.
For instance:
Try 'set all the values grabbed from command line.  these values have defaults that are set in ExampleUtils.vb, you can check there to see them
    device.Channel = phidgetParameters.Channel 'selects the channel on the device to open
    device.DeviceSerialNumber = phidgetParameters.SerialNumber 'selects the device or hub to open
    device.HubPort = phidgetParameters.HubPort 'selects th eport on the hub to open
    device.IsHubPortDevice = phidgetParameters.isHubPortDevice 'is the device a port on a vint hub?

    If phidgetParameters.isRemote Then 'are we trying to open a remote device?
        device.IsRemote = True
        Net.EnableServerDiscovery(ServerType.Device) 'turn on network scan
        If phidgetParameters.Password <> vbNullString And 
           phidgetParameters.ServerName <> vbNullString Then
           
            Net.SetServerPassword(phidgetParameters.ServerName, phidgetParameters.Password)
        End If
    Else
        device.IsLocal = True
    End If

    device.Open() 'open the device specified by the above parameters
Catch ex As PhidgetException
    errorBox.addMessage("Error opening the device: " + ex.Message)
End Try
Might become: 
 Try
    device.Channel = 0
    device.DeviceSerialNumber = 370097
    device.HubPort = 0
    device.IsHubPortDevice = True
    device.IsLocal = True

    device.Open()
Catch ex As PhidgetException
    errorBox.addMessage("Error opening the device: " + ex.Message)
End Try
You can then manipulate the rest of the code as your application requires.
Setting up a New Project
To start a project from scratch, or add Phidget functionality to an existing project, you'll need to include the Phidget .NET library by adding the following lines to your code:
Imports Phidget22
Imports Phidget22.Events
Next, copy Phidget22.NET.dll from the following location:
C:\Program Files\Phidgets\Phidget22\Phidget22.NET.dll
Place your program and the Phidget22.NET.dll file in the same location.
Language vb dll folder.png
Open the command prompt at the folder location and enter the following command:
vbnc /r:Phidget22.NET.dll Module1.vb
This will create an executable file called Module1.exe. Type in the following command to run the example:
mono Module1.exe
The project now has access to Phidgets.

Example Code

Navigate to our Code Samples Page to view and download code samples that are tailored to your specific device. These code samples all use Windows Forms, except for the "Hello World" manager example.

Phidget Programming Basics

To learn more about the structure of the example code, visit our Phidget Programming Basics guide.

API

Phidget22 API

Retrieved from "https://www.phidgets.com/docs/index.php?title=Language_-_Visual_Basic&oldid=35485"