Language - Visual Basic .NET: Difference between revisions

From Phidgets Support
No edit summary
No edit summary
 
(14 intermediate revisions by 4 users not shown)
Line 1: Line 1:
<metadesc>Communicate over USB with sensors, controllers and relays with Phidgets! Our Visual Basic .NET library supports Windows using Visual Studio or Mono.</metadesc>
[[Category:Language]]
[[Category:Language]]
{{OSLang|[[File:icon-Visual Basic Net.png|64x64px|left|link=|alt=]]|Visual Basic .NET, developed by [http://www.microsoft.com Microsoft] is a modern object oriented programming language and the successor to Visual Basic 6.0}}
__NOTOC__
__TOC__
We provide support for the Visual Basic .NET language on the '''Windows''' operating system. We also provide instructions on how to get your project started in a number of common development environments. Select your operating system and preferred development environment below, and follow the instructions to get your project running with Phidgets.


== Introduction ==
If you do not know which development environment you want to use, or your development environment of choice is not listed, we recommend starting with Mono as the simplest path to getting your code running. Visual Studio is the most popular way to build Visual Basic .NET projects, but it also has a steep learning curve.


If this is your first time working with a Phidget, we suggest starting with the Getting Started page for your specific device. This can be found in the user guide for your device. That page will walk you through installing drivers and libraries for your operating system, and will then bring you back here to use VB.NET specifically.
Once you have set up your development environment to run with Phidgets, we recommend you follow our guide on [[Phidget Programming Basics]]. The guide will showcase the fundamentals of programming with Phidgets.
VB.NET is capable of using the complete {{Phidget22API}}, including events. We also provide example code in VB.NET for all Phidget devices.
 
== Setup Guide ==
 
<div class="phd-deck-sequence">
{{PT3_VBNET_CHOOSE}}{{PT3_VBNET_WIN_VS}}{{PT3_VBNET_WIN_MONO}}
</div>


VB.NET with Phidgets is only supported on Windows, and can be used with [[#Visual_Studio_2015|Visual Studio 2015]], [[#Mono|Mono]], or [[#MonoDevelop/Xamarin_Studio|MonoDevelop]].


== Quick Downloads ==
== Quick Downloads ==
If you already know what you're doing and just need the files, you can find them all below.


=== Documentation ===
=== Documentation ===


*{{Phidget22API}} (Select C#/VB.Net from drop-down menu)
*{{Phidget22API}} (Select Visual Basic .NET from drop-down menu)


=== Example Code ===
=== Example Code ===


*{{SampleCode|VBNET|VB.Net Examples}}
*{{SampleCode|VBNET|Visual Basic .NET Examples}}
 
=== Libraries and Drivers ===
 
{{WindowsQuickDownloads}}
 
== Getting Started with VB.NET ==
 
If you are new to writing code for Phidgets, we recommend starting by running, then modifying existing examples. This will allow you to:
{{ExampleCodeReasons}}
 
Instructions are divided up by operating system. Choose:
*[[#Windows(XP/Vista/7)|Windows XP / Vista / 7]]
 
== Windows ==
===Description of Library Files===
Visual Basic .NET programs on Windows depend on the following files, which the installers above put onto your system:
*'''phidget22.dll''' contains the actual Phidget library, which is used at run-time. By default, it is placed in C:\Windows\System32.
*'''Phidget22.NET.dll''' is the Phidget library for .NET framework 2.0 or higher. Your compiler has to know where this file is. By default, it is placed into C:\Program Files\Phidgets\Phidget22. You can either point your compiler to that location, or copy and link to it in a directory for your project workspace.
You can optionally install the following files:
*'''Phidget22.NET.XML''' provides the IntelliSense in-line documentation for the .NET library in Visual Studio/MonoDevelop. This documentation is also visible in the Object Browser in Visual Studio. By default, it is placed into C:\Program Files\Phidgets\Phidget22.
 
Running the examples and writing your own code can be fairly compiler-specific, so we include instructions for each compiler below.
 
===Visual Studio 2015===
 
====Use Our Examples====
Please start by downloading the examples and unpacking them into a folder. Since the examples were written in Visual Studio 2015, you will need to use Visual Studio 2015 or later in order to run the examples. To load all projects in Visual Studio, go to File → Open → Project, and open AllExamples/AllExamples.sln.
 
The easiest way to confirm that your environment is set up properly will be to compile and run the HelloWorld Visual Basic .NET example.
 
Start by setting the HelloWorld project as your start up project.
 
The only thing left to do is to run the example! Click on Debug → Start Debugging. Please note that the projects, by default try to find the Phidget22.NET.dll in the C:\Program Files\Phidgets\Phidget22. If you have it installed in another location, please change the path to the file's location accordingly. If you are receiving an error message regarding that the namespace Phidget22 cannot be found, please re-add the reference to Phidget22.NET.dll. Please see the [[#Write Your Own Code|Write Your Own Code]] section for details.
 
[[Image:VB_VS2015_Run.png|link=|600px]]
 
This program will detect for devices that are attached/detached on the computer. Go ahead, and attach or detach your devices! Here is an example output:
 
[[Image:VB_VS2015_HelloWorld_Output.png|link=|600px]]
 
After confirming that the HelloWorld example is working, you can proceed to run the example for your device. The source file will be named the same as the software object for your device. If you are not sure what the software object for your device is, find your Phidget on our [http://www.phidgets.com webpage], and then check the {{Phidget22API}} documentation for it.
 
Once you have the Visual Basic .NET examples running, we have a [[#Edit the Examples|teaching section]] below to help you follow them.
 
====Write Your Own Code====
 
When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your environment to properly link the Phidget .NET libraries. To begin:
 
1. Generate a new Visual Basic .NET Windows Applications project with a descriptive name such as PhidgetTest.
 
[[Image:VB_VS2015_New_Project.png|link=|600px]]
 
2. Add a reference to the Phidget .NET library.
 
[[Image:VB_VS2015_Add_Reference.png|link=]]
 
3. Click Browse and navigate to the location of Phidget22.NET.dll, and add the file. If you used our installer, these files are installed in C:\Program Files\Phidgets\Phidget22, by default. If you have already done this for a previous project, you should be able to find Phidget22.NET.dll under the Browse → Recent tab.
 
[[Image:VB_VS2015_Add_Reference_2.png|link=|600px]]
 
The project now has access to the Phidget function calls and you are ready to begin coding.
 
The same [[#Edit the Examples|teaching section]] which describes the examples also has further resources for programming your Phidget.
 
===Mono===
 
This section will provide instructions on how to compile using the vbnc compiler.
 
====Use Our Examples====
 
We do not have Visual Basic .NET examples for the Mono framework. Fortunately, you can take a look at the source code for our [[#Example_Code|Visual Studio 2015 examples]] for valuable programming insight. We have a [[#Edit the Examples|teaching section]] below to help you follow them.
 
====Write Your Own Code====
 
When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your compiler to properly link the Phidget .NET library.
 
Place '''Phidget22.NET.dll''' in the same directory as your source code. To compile and build an executable, run:
 
To compile and build an executable, run:
 
<syntaxhighlight lang='bash'>
vbnc /out:example.exe /r:phidget22.NET.dll Example.vb
</syntaxhighlight>
 
If you have the Phidget22.NET.dll installed in another location, please change the path to the file's location accordingly.
 
Afterwards, you will have an executable named example.exe that you can run. Type the following to run the program:
 
<syntaxhighlight lang='bash'>
mono example.exe
</syntaxhighlight>
 
The [[#Edit the Examples|teaching section]] also has further resources for programming your Phidget.
 
===MonoDevelop/Xamarin Studio===
 
====Use Our Examples====
 
Download the [[#Example_Code|examples]] and unpack them into a folder. Here, you can find example programs for all the devices, as well as a HelloWorld program that will work with any Phidget. The source file will be named the same as the software object for your device. If you are not sure what the software object for your device is, find your Phidget on our [http://www.phidgets.com webpage], and then check the {{Phidget22API}} documentation for it.
 
These examples were written in Visual Studio 2015, but are also compatible with MonoDevelop/Xamarin Studio.
 
To load all projects in MonoDevelop/Xamarin Studio, go to File → Open, and open AllExamples/AllExamples.sln
 
This will load all of the examples available for Visual Basic .NET, and then you can set your main project to be the one that matches your device. If you are running under the .NET framework, you can use full examples. Otherwise, if you are running under the Mono framework, please only use the HelloWorld example. The full examples use Windows Forms, which is not completely compatible with Mono's Gtk#.
 
[[Image: VB MonoDevelop setStartup.png|link=]]
 
The only thing left to do is to run the examples! Right click the project, and click on Run With and select the target framework. Please note that the projects, by default try to find the Phidget22.NET.dll in the C\Program Files\Phidgets\Phidget22. If you have it installed in another location, please change the path to the file's location accordingly. If you are receiving an error message regarding that the namespace Phidget22 cannot be found, please re-add the reference to Phidget22.NET.dll. Please see the [[#Write Your Own Code|Write Your Own Code]] section for details.
 
[[Image: VB MonoDelevop Run.png|600px|link=]]
 
Once you have the Visual Basic .NET examples running, we have a [[#Edit the Examples|teaching section]] below to help you follow them.
 
====Write Your Own Code====
 
When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your development environment to properly link the Phidget .NET library. To begin:
 
1. Create a new Visual Basic .NET Console project with a descriptive name such as PhidgetTest.
 
[[Image: VB MonoDelevop NewProject.png|link=|600px]]
 
[[Image: VB MonoDelevop NewProject2.png|link=|600px]]
 
2. Add a reference to the Phidget .NET library.
 
[[Image: VB MonoDelevop EditReferences1.png|link=]]
 
3. Select Phidget22.NET.dll. If you used our installer, by default, this file is placed in C:\Program Files\Phidgets\Phidget22. If it is in another location, please change the path to the file's location accordingly.
 
[[Image: VB MonoDelevop EditReferences2.png|link=|600px]]
 
The project now has access to the Phidget function calls and you are ready to begin coding.
 
The same [[#Edit The Examples|teaching section]] which describes the examples also has further resources for programming your Phidget.
 
== Edit the Examples ==
 
By following the instructions for your operating system and compiler above, you probably now have a working example and want to understand it better so you can change it to do what you want. This teaching section has resources for you to learn from the examples and write your own.
Your main reference for writing VB.NET code will be the {{Phidget22API}} Manual.
 
=== Code Snippets ===
 
The following code snippets describe how to do various general tasks with Phidgets. You should be able to find places in the examples where these snippets exist, and modify them to suit your requirements.
 
==== Step One: Initialize and Open ====
 
The Open() function opens the software object, but not hardware. So, it is not a guarantee you can use the Phidget immediately.
 
For example, if we were using an Digital Input as our device, the create and open calls would look like this:
 
<syntaxhighlight lang='vbnet'>
device = New Phidget22.DigitalInput()
device.Open()
</syntaxhighlight>
 
==== Step Two: Wait for Attachment (plugging in) of the Phidget ====
 
To use the Phidget, it must be plugged in (attached). We can handle this simply by calling open with a number as a parameter in place of the basic open. This function works for any Phidget. This will block until a connection is made to the Phidget, or the specified timeout is exceeded:
 
<syntaxhighlight lang='vbnet'>
device.Open(5000);
</syntaxhighlight>
 
Sometimes, it makes more sense to handle the attachment via an event. This would be in instances where the Phidget is being plugged and unplugged, and you want to handle these incidents. Or, when you want to use event-driven programming because you have a GUI-driven program. In these cases, an event-driven code snippet to handle the attachment might look something like this:
 
<syntaxhighlight lang='vbnet'>
Private Sub device_Attach(ByVal sender As Object, ByVal e As Phidget22.Events.AttachEventArgs) Handles device.Attach
  Dim attachedDevice As Phidget22.Phidget = CType(sender, Phidget22.Phidget)
  Dim serialNumber as Integer
  Dim deviceName as String
  serialNumber = attachedDevice.DeviceSerialNumber;
  deviceName = attachedDevice.DeviceName;
  Console.WriteLine("Hello Device {0},  Serial Number: {1}!", deviceName, serialNumber.ToString());
End Sub
</syntaxhighlight>
 
==== Step Three: Do Things with the Phidget ====
We recommend the use of event driven programming when working with Phidgets. This allows the program to execute other tasks until the Phidget generates a new event. You can hook a custom function into an event trigger like this, using a Digital Input Phidget as an example:
 
<syntaxhighlight lang=vbnet>
Private Sub device_DigitalInputChange(ByVal sender As Object, ByVal e As Phidget22.Events.DigitalInputStateChangeEventArgs) Handles device.StateChange
  textBox1.Text = "State: " + e.State;
End Sub
</syntaxhighlight>
 
Some values can be directly read and set on the Phidget. These functions can be used inside a polling loop as an alternative to event driven programming. The line inside the loop would be something like this, after which you could do something with the value:
 
<syntaxhighlight lang=vbnet>
val = device.State;
 
device.State = true;
</syntaxhighlight>
 
==== Step Four: Close and Delete ====
At the end of your program, be sure to close your device.
 
<syntaxhighlight lang=vbnet>
Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
    device.Close();
End Sub
</syntaxhighlight>
 
== Further Reading ==
 
[[Phidget Programming Basics]] - Here you can find the basic concepts to help you get started with making your own programs that use Phidgets.
 
[[Data Interval/Change Trigger]] - Learn about these two properties that control how much data comes in from your sensors.
 
[[Using Multiple Phidgets]] - It can be difficult to figure out how to use more than one Phidget in your program. This page will guide you through the steps.
 
[[Polling vs. Events]] - Your program can gather data in either a polling-driven or event-driven manner. Learn the difference to determine which is best for your application.


[[Logging, Exceptions, and Errors]] - Learn about all the tools you can use to debug your program.
===Libraries===


[[Phidget Network Server]] - Phidgets can be controlled and communicated with over your network- either wirelessly or over ethernet.
{{AllQuickDownloads}}

Latest revision as of 21:39, 10 August 2023


We provide support for the Visual Basic .NET language on the Windows operating system. We also provide instructions on how to get your project started in a number of common development environments. Select your operating system and preferred development environment below, and follow the instructions to get your project running with Phidgets.

If you do not know which development environment you want to use, or your development environment of choice is not listed, we recommend starting with Mono as the simplest path to getting your code running. Visual Studio is the most popular way to build Visual Basic .NET projects, but it also has a steep learning curve.

Once you have set up your development environment to run with Phidgets, we recommend you follow our guide on Phidget Programming Basics. The guide will showcase the fundamentals of programming with Phidgets.

Setup Guide

VB.NET - Select Development Environment

Select your Development Environment:

Windows

Language - VB.Net

Windows with Visual Studio

Welcome to using Phidgets with Visual Basic .NET! By using Visual Basic .NET, you will have access to the complete Phidget22 API, including events.

Visual Studio is an IDE provided by Microsoft that can be used to develop code in a wide variety of programming languages, including Visual Basic .NET.

Requirements

First, make sure you have the following installed:

● Phidgets Drivers for Windows (see Part 1 of this user guide)

● Microsoft Visual Studio


Nuget

The Phidget22.NET library is now available on nuget.org here. Nuget is the recommended way to install and use the .NET library in Visual Studio. The nuget package bundles the C library on Windows, so there are no other prerequisites that need to be installed. The nuget package adds targets for .NET Core and .NET Standard, so it should be usable from almost any .NET environment which also supports the C library.

Use Our Examples

One of the best ways to start programming with Phidgets is to use our example code as a guide.

VB.Net Code Samples

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.

Use Our Examples

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. Here is an example of a Digital Output channel on a RFID Phidget:

You should now have the example up and running for your device. This would be a good time to play around with the device and experiment with some of its functionality.

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...

Editing the Examples

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.

Write Code

You now have working examples and a project that is configured. This teaching section will help you understand how the examples were written so you can start writing your own code.

Remember: your main reference for writing VB.NET code will be:

● The Phidget22 API documentation

● The VB.Net Example Code

Write Code

Step One: Create And Address

You will need to declare your Phidget object in your code. For example, we can declare a digital input object like this:

ch = New Phidget22.DigitalInput()

Next, we can address which Phidget we want to connect to by setting parameters such as DeviceSerialNumber.

ch.DeviceSerialNumber = 496911

You can find information about all available parameters here or in the API documentation.

Write Code

Step One: Create And Address

Although we will not discuss it in-depth on this page, you should include error handling for all Phidget functions. Here is an example of the previous code with error handling:

Try
  ch = New Phidget22.DigitalInput()
  ch.DeviceSerialNumber = 496911
Catch ex As PhidgetException
  errorBox.addMessage("Error initializing: " + ex.Message)
End Try

Write Code

Step Two: Open And Wait For Attachment

After we have specified which Phidget to connect to, we can open the Phidget object like this:

ch.Open(5000)

To use a Phidget, it must be plugged in (attached). We can handle this by calling Open(timeout), which will block indefinitely until a connection is made, or until the timeout value is exceeded. Simply calling Open does not guarantee you can use the Phidget immediately.

Write Code

Alternately, you could verify the device is attached by using event driven programming and tracking the attach events.

To use events to handle attachments, we have to modify our code slightly:

Private Sub device_Attach(ByVal sender As Object, ByVal e As Phidget22.Events.AttachEventArgs) Handles ch.Attach
  Console.WriteLine("Phidget Attached!");
End Sub

We recommend using this attach handler to set any initialization parameters for the channel such as DataInterval and ChangeTrigger from within the AttachHandler, so the parameters are set as soon as the device becomes available.

Write Code

Step Three: Do Things With The Phidget

We recommend the use of event driven programming when working with Phidgets. In a similar way to handling an attach event as described above, we can also add an event handler for a state change event:

Private Sub device_DigitalInputChange(ByVal sender As Object, ByVal e As Phidget22.Events.DigitalInputStateChangeEventArgs) Handles ch.StateChange
  stateText.Text = "State: " + e.State;
End Sub

If you are using multiple Phidgets in your program, check out our page on Using Multiple Phidgets for information on how to properly address them and use them in events.

If events do not suit your needs, you can also poll the device directly for data using code like this:

state= device.State;
stateText.Text = "State: " + e.State;

Important Note: There will be a period of time between the attachment of a Phidget sensor and the availability of the first data from the device. Any attempts to get this data before it is ready will result in an exception. See more information on this on our page for Unknown Values.

Write Code

Step Three: Do Things With The Phidget

Enumerations: Some Phidget devices have functions that deal with specific predefined values called enumerations. Enumerations commonly provide readable names to a set of numbered options.

Enumerations with Phidgets in Visual Basic .NET will take the form of Phidget22.EnumerationType.Enumeration_Name.

For example, specifying a SensorType to use the 1142 for a voltage input would look like:

Phidget22.VoltageSensorType.PN_1142

and specifying a K-Type thermocouple for a temperature sensor would be:

Phidget22.ThermocoupleType.K

The Phidget error code for timing out could be specified as:

Phidget22.ErrorCode.Timeout

Write Code

Step Four: Close And Delete

At the end of your program, be sure to close and delete your device:

device.Close();

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. To begin:

Create a new Windows Forms Application project:

Setting up a New Project

Next, right-click to add a reference to the Phidget .NET library:

Setting up a New Project

On the following screen, click Browse and navigate to the location of Phidget22.NET.dll:

Setting up a New Project

Finally, to include the Phidget .NET library, add the following lines to main window class file:

Imports Phidget22
Imports Phidget22.Events

Success! The project now has access to Phidgets.

What's Next?

Now that you've set up Phidgets in your programming environment, you should read our guide on Phidget Programming Basics to learn the fundamentals of programming with Phidgets.

Continue reading below for advanced information and troubleshooting for your device.

«
»

Language - VB.Net

Windows with Mono

Welcome to using Phidgets with Visual Basic .NET! By using Visual Basic .NET, you will have access to the complete Phidget22 API, including events.

Mono is an open-source programming environment that aims to make Microsoft .NET applications available across all operating systems.

Requirements

First, make sure you have the following installed:

● Phidgets Drivers for Windows (see Part 1 of this user guide)

Mono


Nuget

The Phidget22.NET library is now available on nuget.org here. Nuget is the recommended way to install and use the .NET library in Visual Studio. The nuget package bundles the C library on Windows, so there are no other prerequisites that need to be installed. The nuget package adds targets for .NET Core and .NET Standard, so it should be usable from almost any .NET environment which also supports the C library.

Use Our Examples

First, download and unpack the HelloWorld example for VB.Net. This example uses the Phidget Manager to list all Phidget channels that can be accessed by your computer:

HelloWorld example

Note: The HelloWorld example is compatible with Mono because it does not use Windows Forms. All other VB.Net examples use Windows Forms.

Use Our Examples

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. Your folder should now look something like this:

Use Our Examples

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

Use Our Examples

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.

Use Our Examples

To download the code samples, visit this page:

VB.Net Code Samples

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.

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...

Editing the Examples

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.

Write Code

You now have working examples and a project that is configured. This teaching section will help you understand how the examples were written so you can start writing your own code.

Remember: your main reference for writing VB.NET code will be:

● The Phidget22 API documentation

● The VB.Net Example Code

Write Code

Step One: Create And Address

You will need to declare your Phidget object in your code. For example, we can declare a digital input object like this:

ch = New Phidget22.DigitalInput()

Next, we can address which Phidget we want to connect to by setting parameters such as DeviceSerialNumber.

ch.DeviceSerialNumber = 496911

You can find information about all available parameters here or in the API documentation.

Write Code

Step One: Create And Address

Although we will not discuss it in-depth on this page, you should include error handling for all Phidget functions. Here is an example of the previous code with error handling:

Try
  ch = New Phidget22.DigitalInput()
  ch.DeviceSerialNumber = 496911
Catch ex As PhidgetException
  errorBox.addMessage("Error initializing: " + ex.Message)
End Try

Write Code

Step Two: Open And Wait For Attachment

After we have specified which Phidget to connect to, we can open the Phidget object like this:

ch.Open(5000)

To use a Phidget, it must be plugged in (attached). We can handle this by calling Open(timeout), which will block indefinitely until a connection is made, or until the timeout value is exceeded. Simply calling Open does not guarantee you can use the Phidget immediately.

Write Code

Alternately, you could verify the device is attached by using event driven programming and tracking the attach events.

To use events to handle attachments, we have to modify our code slightly:

Private Sub device_Attach(ByVal sender As Object, ByVal e As Phidget22.Events.AttachEventArgs) Handles ch.Attach
  Console.WriteLine("Phidget Attached!");
End Sub

We recommend using this attach handler to set any initialization parameters for the channel such as DataInterval and ChangeTrigger from within the AttachHandler, so the parameters are set as soon as the device becomes available.

Write Code

Step Three: Do Things With The Phidget

We recommend the use of event driven programming when working with Phidgets. In a similar way to handling an attach event as described above, we can also add an event handler for a state change event:

Private Sub device_DigitalInputChange(ByVal sender As Object, ByVal e As Phidget22.Events.DigitalInputStateChangeEventArgs) Handles ch.StateChange
  stateText.Text = "State: " + e.State;
End Sub

If you are using multiple Phidgets in your program, check out our page on Using Multiple Phidgets for information on how to properly address them and use them in events.

If events do not suit your needs, you can also poll the device directly for data using code like this:

state= device.State;
stateText.Text = "State: " + e.State;

Important Note: There will be a period of time between the attachment of a Phidget sensor and the availability of the first data from the device. Any attempts to get this data before it is ready will result in an exception. See more information on this on our page for Unknown Values.

Write Code

Step Three: Do Things With The Phidget

Enumerations: Some Phidget devices have functions that deal with specific predefined values called enumerations. Enumerations commonly provide readable names to a set of numbered options.

Enumerations with Phidgets in Visual Basic .NET will take the form of Phidget22.EnumerationType.Enumeration_Name.

For example, specifying a SensorType to use the 1142 for a voltage input would look like:

Phidget22.VoltageSensorType.PN_1142

and specifying a K-Type thermocouple for a temperature sensor would be:

Phidget22.ThermocoupleType.K

The Phidget error code for timing out could be specified as:

Phidget22.ErrorCode.Timeout

Write Code

Step Four: Close And Delete

At the end of your program, be sure to close and delete your device:

device.Close();

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. To begin:

To include the Phidget .NET library, simply add the following lines to your code:

Imports Phidget22
Imports Phidget22.Events

Setting up a New Project

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. Your folder should now look something like this:

Setting up a New Project

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

Success! The project now has access to Phidgets.

What's Next?

Now that you've set up Phidgets in your programming environment, you should read our guide on Phidget Programming Basics to learn the fundamentals of programming with Phidgets.

Continue reading below for advanced information and troubleshooting for your device.

«
»


Quick Downloads

If you already know what you're doing and just need the files, you can find them all below.

Documentation

Example Code

Libraries