Language - C Sharp: Difference between revisions

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The project now has access to Phidgets. Next, view the [[#Write Code | write your own code]] section located below.
The project now has access to Phidgets. Next, view the [[#Write Code | write your own code]] section located below.
== Write Code ==


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.
==Write Code==
Your main reference for writing C# code will be the {{Phidget22API}} Manual.
{{WriteCode_Intro}}
 
 
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 ====
==== 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.
You will need to declare your Phidget variable in your code. For example, we can declare a Phidget Digital Output like this:
 
For example, if we were using an Digital Input as our device, the create and open calls would look like this:
 
<syntaxhighlight lang=csharp>
<syntaxhighlight lang=csharp>
using Phidget22;
DigitalOutput ch;
using Phidget22.Events;
</syntaxhighlight>


namespace Program
The object name for any Phidget is listed in the {{Phidget22API}} manual. Every Phidget also inherits functionality from the Phidget base class.
{
    class Code
    {
        static void Main(string[] args)
        {
            try
            {


                // Declare a DigitalInput object
                DigitalInput device = new DigitalInput();


                // Hook in any event handlers
Next, the Phidget object needs to be initialized and opened:
                // ...
<syntaxhighlight lang=cSharp>
 
ch = new DigitalInput();
                // Open the device
ch.Open();
                device.Open();
 
            }
            catch (PhidgetException ex) { Console.WriteLine(ex.Description); }
        }
    }
}
</syntaxhighlight>
</syntaxhighlight>


==== Step Two: Wait for attachment (plugging in) of the Phidget ====
==== Step Two: Wait for attachment 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:
Simply calling open does not guarantee you can use the Phidget immediately. To use a Phidget, it must be plugged in (attached). We can handle this by using event driven programming and tracking the attach events. Alternatively, we can call the following function:


<syntaxhighlight lang=C>
<syntaxhighlight lang=CSharp>
device.Open(5000);
ch = new DigitalInput();
ch.Open(5000); //wait for attach for 5 seconds, if not time out
</syntaxhighlight>
</syntaxhighlight>
Waiting for attachment will block indefinitely until a connection is made, or until the timeout value is exceeded.


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:


To use events, we have to modify our code slightly:
<syntaxhighlight lang=CSharp>
<syntaxhighlight lang=CSharp>
void attachEventHandler(object sender, Phidget22.Events.AttachEventArgs e) {
ch = new DigitalInput();
{
ch.Attach += onAttachHandler;
  Phidget attachedDevice = (Phidget)sender;
ch.Open();
  int serialNumber = attachedDevice.DeviceSerialNumber;
  string deviceName = attachedDevice.DeviceName;
  Console.WriteLine("Hello Device {0},  Serial Number: {1}!", deviceName, serialNumber.ToString());
}
</syntaxhighlight>
</syntaxhighlight>


And the code to set up the event handler within the code opening your device might look like:
Next, we have to declare the function that will be called when an attach event is fired - in this case the function onAttachHandler will be called.
 
<syntaxhighlight lang=CSharp>
<syntaxhighlight lang=CSharp>
//Code for -creating- device here....
void onAttachHandler (object sender, Phidget22.Events.AttachEventArgs e){
 
  attachedText.Text = "Attached";
device.Attach += attachEventHandler;
}
 
//Code for -opening- device here....
</syntaxhighlight>
</syntaxhighlight>


==== Step Three: Do things with the Phidget ====
==== 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:
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 add an event handler with the following code:
 
<syntaxhighlight lang=csharp>
<syntaxhighlight lang=csharp>
device.StateChange += input_change;
ch = new DigitalInput();
ch.Attach += onAttachHandler;
ch.StateChange += onStateChangeHandler;
ch.Open();
</syntaxhighlight>
</syntaxhighlight>


The input_change method is defined as follows:
This code will connect a function and an event. In this case, the onStateChangeHandler function will be called when there has been a change to the devices input. Next, we need to create the onStateChangeHandler function:
 
<syntaxhighlight lang=cSharp>
<syntaxhighlight lang=csharp>
void onStateChangeHandler(object sender, Phidget22.Events.DigitalInputStateChangeEventArgs e) {
void input_change(object sender, Phidget22.Events.DigitalInputStateChangeEventArgs e) {
     stateText.Text = "State: " + e.State;
     textBox1.Text = "State: " + e.State;
}
}
</syntaxhighlight>
</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=csharp>
If events do not suit your needs, you can also poll the device directly for data using code like this:
bool val = device.State;
<syntaxhighlight lang=cSharp>
 
stateText.Text = "State: " + ch.State;
device.State = true;
</syntaxhighlight>
</syntaxhighlight>


==== Step Four: Close and delete ====
==== Step Four: Close and delete ====
At the end of your program, be sure to close your device.
At the end of your program, be sure to close your device.
 
<syntaxhighlight lang=cSharp>
<syntaxhighlight lang=csharp>
ch.Close()
private void Form1_FormClosing(object sender, FormClosingEventArgs e)  {
    Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        If device.Attached Then
            device.Close()
        End If
    End Sub
}
</syntaxhighlight>
</syntaxhighlight>


Revision as of 19:31, 9 June 2017

Quick Downloads

Documentation

Example Code

Libraries

Getting started with C#

Welcome to using Phidgets with C#! By using C#, you will have access to the complete Phidget22 API, including events. We also provide example code in C# for all Phidget devices.

If you are developing for Windows, keep reading. Otherwise, select your operating system to jump ahead:

Windows

If you haven't already, please visit the Windows page before you continue reading. There you will be instructed on how to properly set up your Windows machine so you can follow the guides below!

Visual Studio

Use our examples

One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples, you will need to download and install Microsoft Visual Studio.


Now that you have Microsoft Visual Studio installed, select an example that will work with your Phidget:


Open the example project and start the example by pressing the Start button:


Csharp visualstudio run.png


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:


Csharp visualstudio rfid.PNG


You should now have the example up and running for your device. Play around with the device and experiment with some of the functionality. When you are ready, the next step is configuring your project and writing your own code!

Configure your 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:


CSharp VS2015 New Project.png


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


CSharp VS2015 Add Reference.png


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

  • C:\Program Files\Phidgets\Phidget22\Phidget22.NET.dll


CSharp VS2015 Add Reference 2.png


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

using Phidget22;
using Phidget22.Events;

Success! The project now has access to Phidgets. Next, view the write your own code section located below.

Mono

Use our examples

One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples, you will need to download and install Mono for Windows.


Now that you have Mono installed, download and unpack the HelloWorld example for C#:

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


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:

Csharp mono folder.PNG


Open the command prompt at the folder location and enter the following command: 

mcs /r:Phidget22.NET.dll Program.cs

This will create an executable file called Program.exe. Type in the following command to run the example: 

mono Program.exe


Csharp mono.PNG


You should now have the example up and running. When you are ready, the next step is configuring your project and writing your own code!

Configure your project

When you are building a project from scratch, or adding Phidget functionality to an exisiting project, you'll need to configure your development environment to properly link the Phidget .NET library.

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

using Phidget22;
using Phidget22.Events;

You can now compile the file as shown in the previous section.


The project now has access to Phidgets. Next, view the write your own code section located below.

MonoDevelop/Xamarin Studio

Use our examples

One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples, you will need to download and install Xamarin Studio for Windows.


Now that you have Xamarin Studio installed, select an example that will work with your Phidget:


Next, open the example project:


Csharp xamarin.PNG


Right click the project, and click Run Item:


Chsarp xamarin run.png


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:


Csharp visualstudio rfid.PNG


You should now have the example up and running for your device. Play around with the device and experiment with some of the functionality. When you are ready, the next step is configuring your project and writing your own code!

Configure your project

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:


Create a new .NET project:


Csharp xamarin newproject.PNG


Csharp xamarin nameproject.PNG


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


Csharp xamarin editreference.png


On the following screen, select Phidget22.NET.dll:


Csharp xamarin addreference.PNG


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

  using Phidget22;
  using Phidget22.Events;

Success! The project now has access to Phidgets. Next, view the write your own code section located below.

macOS

If you haven't already, please visit the macOS page before you continue reading. There you will be instructed on how to properly set up your macOS machine so you can follow the guides below!

Mono

Use our examples

One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples, you will need to download and install Mono for macOS. You will also need a copy of Phidget22.NET.dll.


Now that you have Mono installed and Phidget22.NET.dll on hand, download and unpack the HelloWorld example for C#:

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


Finally, you need to create a configuration file. Create a new file in the same directory as the example you wish to compile and name it Phidget22.NET.dll.config. Copy the content below to the file. 

  <configuration>
  <dllmap dll="phidget22.dll" target="/Library/Frameworks/Phidget22.framework/Versions/Current/Phidget22" />
  </configuration>

Your project folder should now look like this:


Csharp macos mono folder.png


To compile the program, enter the following command in the terminal: 

mcs Program.cs -r:Phidget22.NET.dll

An executable file will be created. Run the program using mono: 

mono Program.exe


Csharp macos mono run.png


You should now have the example up and running for your device. Play around with the device and experiment with some of the functionality. When you are ready, the next step is configuring your project and writing your own code!

Configure your project

When you are building a project from scratch, or adding Phidget functionality to an exisiting project, you'll need to configure your development environment to properly link the Phidget .NET library.

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

using Phidget22;
using Phidget22.Events;

You can now compile the file as shown in the previous section.


The project now has access to Phidgets. Next, view the write your own code section located below.

Linux

If you haven't already, please visit the Linux page before you continue reading. There you will be instructed on how to properly set up your Linux machine so you can follow the guides below!

Mono

Use our examples

One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples, you will need to download and install Mono. You can do this by entering the following command in the terminal: 

apt-get install mono-complete

You will also need a copy of Phidget22.NET.dll.


Now that you have Mono installed and Phidget22.NET.dll on hand, download and unpack the HelloWorld example for C#:

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


Your project folder should now look like this:

Csharp linux folder.PNG


Finally, to compile the program, enter the following command in the terminal: 

mcs Program.cs -r:Phidget22.NET.dll

An executable file will be created. Run the program using mono: 

mono Program.exe


Csharp linux mono run.PNG


You should now have the example up and running for your device. Play around with the device and experiment with some of the functionality. When you are ready, the next step is configuring your project and writing your own code!

Configure your project

When you are building a project from scratch, or adding Phidget functionality to an exisiting project, you'll need to configure your development environment to properly link the Phidget .NET library.

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

using Phidget22;
using Phidget22.Events;

You can now compile the file as shown in the previous section.


The project now has access to Phidgets. Next, view the write your own code section located below.

Write Code

By following the instructions for your operating system and compiler above, 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 {{{1}}} code will be the Phidget22 API Manual and the example code.

Step One: Initialize and open

You will need to declare your Phidget variable in your code. For example, we can declare a Phidget Digital Output like this: 

DigitalOutput ch;

The object name for any Phidget is listed in the Phidget22 API manual. Every Phidget also inherits functionality from the Phidget base class.


Next, the Phidget object needs to be initialized and opened: 

ch = new DigitalInput();
ch.Open();

Step Two: Wait for attachment of the Phidget

Simply calling open does not guarantee you can use the Phidget immediately. To use a Phidget, it must be plugged in (attached). We can handle this by using event driven programming and tracking the attach events. Alternatively, we can call the following function: 

ch = new DigitalInput();
ch.Open(5000); //wait for attach for 5 seconds, if not time out

Waiting for attachment will block indefinitely until a connection is made, or until the timeout value is exceeded.


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

ch = new DigitalInput();
ch.Attach += onAttachHandler;
ch.Open();

Next, we have to declare the function that will be called when an attach event is fired - in this case the function onAttachHandler will be called. 

void onAttachHandler (object sender, Phidget22.Events.AttachEventArgs e){
  attachedText.Text = "Attached";
}

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 add an event handler with the following code: 

ch = new DigitalInput();
ch.Attach += onAttachHandler;
ch.StateChange += onStateChangeHandler;
ch.Open();

This code will connect a function and an event. In this case, the onStateChangeHandler function will be called when there has been a change to the devices input. Next, we need to create the onStateChangeHandler function: 

void onStateChangeHandler(object sender, Phidget22.Events.DigitalInputStateChangeEventArgs e) {
    stateText.Text = "State: " + e.State;
}


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

stateText.Text = "State: " + ch.State;

Step Four: Close and delete

At the end of your program, be sure to close your device. 

ch.Close()

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.

Phidget Network Server - Phidgets can be controlled and communicated with over your network- either wirelessly or over ethernet.

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