Products for USB Sensing and Control

Language - C Sharp

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C# is a modern, object-oriented programming language developed by Microsoft.

Contents


Introduction

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 C# specifically.

C# is capable of using the complete Phidget API, including events. We also provide example code in C# for all Phidget devices.

C# can be developed with the .NET or Mono framework. Both of the frameworks are supported on Windows. For Linux and OS X, only the Mono framework can be used. We provide instructions on how to set up your environment/compilers for Visual Studio 2005/2008/2010, Visual Studio 2003, MonoDevelop and the Mono command line compilers.

You can compare C# with our other supported languages.

Quick Downloads

Just need the C# documentation, drivers, libraries, and examples? Here they are:

Documentation

Example Code

Libraries and Drivers

Getting started with C#

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

  • Make sure your libraries are properly linked
  • Go from source code to a test application as quickly as possible
  • Ensure your Phidget is hooked up properly

Instructions are divided up by operating system. Choose:

Windows (XP/Vista/7/8)

Description of Library Files

C# programs on Windows depend on the following files, which the installers above put onto your system:

  • phidget21.dll contains the actual Phidget library, which is used at run-time. By default, it is placed in C:\Windows\System32.

You will also need one of the following two files, depending on the .NET framework version you are targeting:

  • Phidget21.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. You can either point your compiler to that location, or copy and link to it in a directory for your project workspace.
  • Phidget21.NET1.1.dll is the Phidget library for .NET framework 1.1. Your compiler has to know where this file is. By default, is is placed into C:\Program Files\Phidgets. 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:

  • Phidget21.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.
  • Policy.2.1.Phidget21.NET.dll is the policy assembly for Phidget21.NET.dll. Our installer places this file in the Global Assembly Cache(GAC) directory. It directs any programs compiled against version 2.1.0 or higher of Phidget21.NET.dll to use the most recent installed version.

If you do not want to use our installer, you can download the five files.

Running the examples and writing your own code can be fairly compiler-specific, so we include instructions for each compiler below.

Visual Studio 2005/2008/2010

Microsoft makes free versions of Visual Studio available known as Express Editions. The Express editions are suitable for most applications, but are limited in features for more complex applications. Please see Microsoft Visual Studio for more information.

Use Our Examples

Please start by downloading the examples and unpacking them into a folder. While these examples were written in Visual Studio 2005 and 2008, Visual Studio 2010 will easily open and upgrade them. To load all projects in Visual Studio, go to File → Open → Project, and open AllExamples/AllExamples.sln or AllExamples/AllExamples_vs2008.sln for Visual Studio 2005 and 2008, respectively.

If you are opening the Phidget examples in Visual Studio 2010, you will need to go through the Visual Studio Conversion Wizard to convert the 2005 or 2008 project.

Conversion Wizard

The easiest way to confirm that your environment is set up properly will be to compile and run the HelloWorld C/C++ 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 Phidget21.NET.dll in the C:\Program Files\Phidgets. 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 Phidgets cannot be found, please re-add the reference to Phidget21.NET.dll. Please see the Write Your Own Code section for details.

Run

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:

HelloWorld Output

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 webpage, and then check the API documentation for it.

Once you have the C# examples running, we have a 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 C# libraries. To begin:

1. Generate a new Visual C# Windows Applications project with a descriptive name such as PhidgetTest.

New Project

2. Add a reference to the Phidget .NET library.

Add Reference

3. Under the .NET tab, select Phidget21.NET.dll. If you used our installer, these files are installed in C:\Program Files\Phidgets, by default. If it does not appear in this list, then you can browse to the Phidget Framework installation directory and add the file.

Add Reference

4. Then, in your code, you will need to include the Phidget .NET library:

  using Phidgets;
  using Phidgets.Events;


The project now has access to the Phidget function calls and you are ready to begin coding.

The same teaching section which describes the examples also has further resources for programming your Phidget.

Visual Studio 2003

Use Our Examples

1. Download the examples and unpack them into a folder. Here, you can find the HelloWorld example which works with any Phidget. You can also find example programs for all the devices. 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 webpage, and then check the API documentation for it.

As the examples were written in newer versions of Visual Studio, Visual Studio 2003 is not able to open the examples. Fortunately, you can import the simple examples to a Visual Studio 2003 project. It will be difficult to import the full examples as you will need to recreate the GUI components.

2. Next, a new project will need to be created. Generate a new Visual C# console application project with a descriptive name such as PhidgetTest.

New Project

3. Add a reference to the Phidget .NET library.

Add Reference

4. Under the .NET tab, select Phidget21.NET1.1.dll. If you used our installer, by default, this file is placed in C:\Program Files\Phidgets. If it is in another location, please change the path to the file's location accordingly.

Add Reference

5. To import the simple example program into your project, please: open up Class1.cs.

6. Traverse to the example in Windows Explorer and locate the Program.cs file.

Source Code

7. Copy and paste the contents from that file into Class1.cs.

8. Comment out the following line as it is not supported in .NET 1.1:

  using System.Collections.Generic;

Source Code

9. Now, you can run the example. Click on Debug → Start.

Run

Once you have the C# examples running, we have a 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. Please see the Use Our Examples section for instructions.

Then, in your code, you will need to include the Phidget .NET library:

  using Phidgets;
  using Phidgets.Events;

The project now has access to the Phidget function calls and you are ready to begin coding.

The same 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 mcs compiler. Other compilers such as gmcs, smcs, and dmcs all work in the same way.

Use Our Examples

Download the examples and unpack them into a folder. Here, you can find the HelloWorld program that will work with any Phidget. You will also find example programs for all the devices. 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 webpage, and then check the API documentation for it..

Please only use the simple examples. The full examples uses Windows Forms, which Mono and the Gtk# toolkit are not completely compatible with. Locate the Program.cs file as this contains the example source code. Copy the file into your working directory, and rename it to example.cs.

Place the Phidget21.NET.dll in the same directory as your source code.

To compile and build an executable, run:

mcs /out:example.exe /r:phidget21.NET.dll example.cs

If you have the Phidget21.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:

mono example.exe

Once you have the C# examples running, we have a 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. Please see the Use Our Example section for instructions.

In your code, you will need to include the Phidget .NET library:

  using Phidgets;
  using Phidgets.Events;


The project now has access to the Phidget function calls and you are ready to begin coding.

The same teaching section which describes the examples also has further resources for programming your Phidget.

MonoDevelop

Use Our Examples

Download the 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 webpage, and then check the API documentation for it.

These examples were written in Visual Studio 2005 and 2008, but are also compatible with MonoDevelop.

To load all projects in MonoDevelop, go to File → Open, and open AllExamples/AllExamples.sln

This will load all of the examples available for C#, 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 either the full or simple examples. Otherwise, if you are running under the Mono framework, please only use the simple examples. The full examples uses Windows Forms, which is not completely compatible with Mono's Gtk#.

Start Up Project

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 Phidget21.NET.dll in the C\Program Files\Phidgets. 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 Phidgets cannot be found, please re-add the reference to Phidget21.NET.dll. Please see the Write Your Own Code section for details.

Run As

Once you have the C# examples running, we have a 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 C# empty project with a descriptive name such as PhidgetTest.

New Project

2. Add a reference to the Phidget .NET library.

Add Reference

3. Select Phidget21.NET.dll. If you used our installer, by default, this file is placed in C:\Program Files\Phidgets. If it is in another location, please change the path to the file's location accordingly.

Add Reference

4. Then, in your code, you will need to include the Phidget .NET library:

  using Phidgets;
  using Phidgets.Events;

The project now has access to the Phidget function calls and you are ready to begin coding.

The same teaching section which describes the examples also has further resources for programming your Phidget.

OS X

The first thing you are going to need to do is install Mono (Note that Mono is only available for Intel Macs and not PowerPC). You will need both the SDK and the runtime.

Then, you will need the Phidget .NET libraries. These are part of the Windows library zip file download:

Extract the library zip file. Descriptions for the files are available on the OS - Windows page, but for now we only need the Phidget21.NET.dll file to run the Phidget C# examples in Mono. So remember where you unzipped these Windows libraries - you will need to copy the Phidget21.NET.dll file into your example directory shortly.

Next, you'll want to download and extract the Phidget C# Examples (For Windows, not for .NET Compact):

One more thing needs to be done before you can compile and run the examples. You need to set up a special configuration file so that Mono knows where to find the phidget21.dll. Since Mac does not use dll's you need to redirect it to the appropriate file. Create a new file in the same directory as the example you wish to compile and name it Phidget21.NET.dll.config. Put the following into the file:

<configuration>
	<dllmap dll="phidget21.dll" target="/Library/Frameworks/Phidget21.framework/Versions/Current/Phidget21" />
</configuration>

All that is left is to compile and run the code. When compiling, you need to link to the Phidget library. As the Phidget21.NET file is an "additional assembly" in C#/Mono, you can link to the assembly using the -r "reference" switch:

gmcs Program.cs -r:Phidget21.NET.dll

This will compile a *.exe file - in this case, Program.exe. This you can then run under Mono:

mono Program.exe

If you will be compiling with an IDE such as GTK# or MonoDevelop, we don't have explicit instructions by IDE for OS X. However, you will probably find the MonoDevelop section in the Windows portion above useful.

Linux

C# has support on Linux through the Mono framework.

Use Our Examples

The first step in using C# with Phidgets on Linux is to make sure that you have all of Mono installed. Although you probably have already done this if you're a C# programmer, you want to make sure you have all of the packages you'll need. Try:

sudo apt-get mono-complete

Next, you'll want to install the main Phidget Libraries. Compile and install them as explained on the main Linux page. That Linux page also describes the different Phidget files, their installed locations, and their roles.

Then, you will need the Phidget .NET libraries. These are part of the Windows library zip file download:

Extract the library zip file. Descriptions for the files are available on the OS - Windows page, but for now we only need the Phidget21.NET.dll file to run the Phidget C# examples in Mono. So remember where you unzipped these Windows libraries - you will need to copy the Phidget21.NET.dll file into your example directory shortly.

Next, you'll want to download and extract the Phidget C# Examples (For Windows, not for .NET Compact):

To check that your Linux, Phidget, and Mono setup is all working together, you'll want to run the C# examples. Specifically, you'll want to run the simple C# examples. You can either use the HelloWorld program that will work with any Phidget, or you can find the source code 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 webpage, and then check the API documentation for it.

Let's say you're running the Temperature Sensor example (for the 1048 or 1051). The source code for the example is in the directory:

TemperatureSensorExamplesTemperatureSensor-simpleTemperatureSensor-simpleProgram.cs

Other examples will be in directories named appropriately for their software object name. Once you have found the example you want to run, copy the Phidget21.NET.dll file that you unzipped earlier into that example directory where the Program.cs file is.

Then, compile the code. When compiling, you need to link to the Phidget library. As the Phidget21.NET file is an "additional assembly" in C#/Mono, you can link to the assembly using the -r "reference" switch:

gmcs Program.cs -r:Phidget21.NET.dll

This will compile a *.exe file - in this case, Program.exe. This you can then run under Mono:

sudo mono Program.exe

Remember that the sudo is needed unless you have your udev rules set on your Linux system.

If you will be compiling with an IDE such as GTK# or MonoDevelop, we don't have explicit instructions by IDE for Linux. However, you will probably find the MonoDevelop section in the Windows portion above useful.

Write Your Own Code

When writing your code from scratch, you start it as you would any C# code on Linux, such as within a text editor like Emacs, Vi, Gedit, or Kate. In your .cs source code file, you must include a reference to the Phidget Library:

using Phidgets; 
using Phidgets.Events;

Then, you would compile your completed C# code the same way as the examples above.

Mono also has a few different IDEs which you can use to develop code, and these are especially useful if you are doing GUI development. We provide instructions for MonoDevelop - one such IDE - being used under Windows.

To learn how to write your own code for your Phidget, and to learn more about our API, we have a teaching section to help you follow the provided C# examples and which has resources such as the API reference.

Windows CE

Description of Library Files

C# programs on Windows depend on the following files, which the installers above put onto your system:

  • phidget21.dll contains the actual Phidget library, which is used at run-time. By default, it is placed in C:\Windows\System32.

You will also need one of the following two files, depending on the .NET framework version you are targeting:

  • Phidget21.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. You can either point your compiler to that location, or copy and link to it in a directory for your project workspace.
  • Phidget21.NET1.1.dll is the Phidget library for .NET framework 1.1. Your compiler has to know where this file is. By default, it is placed into C:\Program Files\Phidgets. 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:

  • Phidget21.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.
  • Policy.2.1.Phidget21.NET.dll is the policy assembly for Phidget21.NET.dll. Our installer places this file in the Global Assembly Cache(GAC) directory. It directs any programs compiled against version 2.1.0 or higher of Phidget21.NET.dll to use the most recent installed version.

If you do not want to use our installer, you can download the five files.

Running the examples and writing your own code can be fairly compiler-specific, so we include instructions for each compiler below.

Visual Studio 2005/2008/2010

Microsoft makes free versions of Visual Studio available known as Express Editions. The Express editions are suitable for most applications, but are limited in features for more complex applications. Please see Microsoft Visual Studio for more information.

Use Our Examples

Please start by downloading the examples and unpack them into a folder. While these examples were written in Visual Studio 2005 and 2008, Visual Studio 2010 will easily open and upgrade them. To load all projects in Visual Studio, go to File → Open → Project, and open AllExamples/AllExamples.sln or AllExamples/AllExamples_vs2008.sln for Visual Studio 2005 and 2008, respectively.

If you are opening the Phidget examples in Visual Studio 2010, you will need to go through the Visual Studio Conversion Wizard to convert the 2005 or 2008 project. Conversion Wizard

The easiest way to confirm that your environment is set up properly will be to compile and run the HelloWorld C/C++ 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 Phidget21.NET.dll in the C:\Program Files\Phidgets. 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 Phidgets cannot be found, please re-add the reference to Phidget21.NET.dll. Please see the Write Your Own Code section for details.

Run

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:

HelloWorld Output

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 webpage, and then check the API documentation for it. Please ensure that you have set your start up project to be the one that matches your device before compiling.

Once you have the C# examples running, we have a 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 C# libraries. To begin:

1. Generate a new Visual C# Windows Applications project with a descriptive name such as PhidgetTest.

New Project

2. Add a reference to the Phidget .NET library.

Add Reference

3. Under the .NET tab, select Phidget21.NET.dll. If you used our installer, these files are installed in C:\Program Files\Phidgets, by default. If it does not appear in this list, then you can browse to the Phidget Framework installation directory and add the file.

Add Reference

4. Then, in your code, you will need to include the Phidget .NET library:

  using Phidgets;
  using Phidgets.Events;


The project now has access to the Phidget function calls and you are ready to begin coding.

The same teaching section which describes the examples also has further resources for programming your Phidget.

Follow 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 C# code will be our C# API information, with syntax for all of our functions:

  • .NET API (This is the complete set of functions you have available for all Phidgets)
  • Device Specific APIs - The one for your Phidget can be found in its user guide.

To learn the details behind opening, configuring, using, and closing your Phidget, try the General Phidget Programming page. That page also describes using the Phidget in an event-driven manner and in a traditional manner, both of which are available in C#.

Example Flow

The Hello World example has this general structure so you can follow along. We also have an in-depth general introduction to writing Phidget code (like open, read data, etc), as well as the .NET API for specific syntax:

// ----- Event and Other Functions -----

Create any Language-Specific Functions (exception handling)

Create General Attach, Detach, and Error Handling Functions:

On attach: Print Hello Message
On detach: Print Goodbye Message

 

In C#, you can name these event functions whatever you like. You will add them to the Phidget .NET library in the Main Code section. This hooks them into the actual events when they occur.

In the example code, the event functions common to all Phidgets are things like attach, detach, and error handling.
Other event functions will be specific to each device, like when a tag is read on an RFID board, or when a sensor value changes on an Interface Kit.

// ----- Main Code -----

Create Manager Software Object
Hook Event Functions created above to Device
Open Device

Wait for 'Enter' key character input
Handle on-going attach and detach events
Print Hello and Goodbye messages
Exit upon input

Close Device

Delete Device

 

Creating a Phidget software object in C# is specific to the Phidget. For a Phidget Spatial, for example, this would involve creating a Spatial object. The examples show how to do this and other API functions.

The object provides device specific methods and properties which are available from the API for your specific Phidget.

Code Snippets

Specific calls in C# will differ in syntax from those on the General Phidget Programming page, but the concepts stay the same.  

It may help to have the General Phidget Programming page and this section open at the same time, because they parallel each other and you can refer to the C# syntax.  However, many additional concepts are covered on the General Phidget Programming page on a high level, such as using multiple Phidgets, handling errors, and different styles of programming.

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.

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 and General Phidget Programming discusses all of the available modes that open provides.

For example, if we were using a Temperature Sensor board as our device, the general calls would look like this:

using Phidgets;
using Phidgets.Events;
// using.....
 
namespace Program {
    class Code {
        static void Main(string[] args) {
            try {
 
                // Declare a TemperatureSensor object
                TemperatureSensor device = new TemperatureSensor(); 
 
                // Hook in any event handlers
                // ...
 
                // Open the device
                device.open();
 
            } catch (PhidgetException ex) { Console.WriteLine(ex.Description); }
        }
    }
}

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

To use the Phidget, it must be plugged in (attached). We can handle this by using event driven programming and tracking the AttachEvents and DetachEvents, or we can handle this by calling waitForAttachment. This function works for any Phidget. WaitForAttachment will block indefinitely until a connection is made to the Phidget, or an optional timeout is exceeded:

  device.open();
  Console.WriteLine("Waiting for TemperatureSensor to be attached....");
  device.waitForAttachment();

One important thing to remember is that when working with Phidgets, a local connection will reserve the device until closed. This means only one program can access the Phidget locally. Many computers can access one Phidget over the Phidget WebService.

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 the Interface Kit Phidget as an example:

ifKit.SensorChange += new SensorChangeEventHandler(ifKit_SensorChange);

The ifKit_SensorChange method is defined as follows:

void ifKit_SensorChange(object sender, SensorChangeEventArgs e) {
   textBox1.Text = "Index " + e.Index + " Value: " + e.Value;
}

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:

int val = device.sensors[0].Value;

Step Four: Close and Delete

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.

private void Form1_FormClosing(object sender, FormClosingEventArgs e)  {
    ifKit.SensorChange -= new SensorChangeEventHandler(ifKit_SensorChange);
    //run any events in the message queue
    Application.DoEvents();
    ifKit.close();
}

More How-To's

The General Phidget Programming page gives more information about:

The complete set of functions you have available for all Phidgets can be found in the .NET API. You can also find more description on any device-specific function in the Device API page for your specific Phidget, which can be found in it's user guide.

Common Problems and Solutions/Workarounds

All Operating Systems: The Phidgets.Events.ErrorEventHandler conflicts with System.IO.ErrorEventHandler.

using System.IO;
using Phidgets;
using Phidgets.Events;
...
spatial.Error += new ErrorEventHandler(spatial_Error);
 
...
void spatial_Error(object sender, ErrorEventArgs e){
   ...
}

The above code produces the following errors:

'ErrorEventHandler' is an ambiguous reference between 'System.IO.ErrorEventHandler' and 'Phidgets.Events.ErrorEventHandler'.

and

'ErrorEventArgs' is an ambiguous reference between 'System.IO.ErrorEventArgs' and 'Phidgets.Events.ErrorEventArgs'.

The error is due to the System.IO and Phidgets.Events namespaces both having a class called ErrorEventHandler.

To get around this issue, use the fully qualified namespace when referring to the ErrorEventHandler and ErrorEventArgs classes:

using System.IO;
using Phidgets;
using Phidgets.Events;
...
spatial.Error += new Phidgets.Events.ErrorEventHandler(spatial_Error);
...
 
void spatial_Error(object sender, Phidgets.Events.ErrorEventArgs e){
   ...
}
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