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Enumerate WIA Devices
Take the following steps to create and run a program that enumerates the available WIA devices on your machine.
  1. Start Visual Studio .NET.
  2. Choose File->New->Project… from the menu.
  3. In the New Project dialog box, choose either "Visual C# Projects" or "Visual Basic Projects" in the Projects Type List, and choose "Windows Application " in the Templates List.
  4. Type the project name as "Enumerate WIA Devices" in the Project Name field, and then choose OK. If desired, type a new location for your project or select a directory using the Browse button, and then choose OK.
  5. In the "Solution Explorer" window, right-click on the "References" folder, and select "Add Reference…" from the context menu. In the "Add Reference" dialog box, select the ".NET" tab and browse to Leadtools For .NET "\LEAD Technologies\LEADTOOLS 16.5\Bin\DotNet\Win32 " folder and select the following DLLs:
    • Leadtools.Wia.dll
    Click the Select button and then press the OK button to add the above DLL to the application.
  6. Go to the toolbox (View->Toolbox) and Drag and drop 1 instance of Button control to the top of the form and set the following properties for them:
    TextName
    Enumerate WIA DevicesbtnEnumWiaDevices
  7. Switch to Form1 code view (right-click Form1 in the solution explorer then select View Code ) and add the following lines at the beginning of the file:

    [Visual Basic]

    
    Imports Leadtools.Wia
    
    [C#]
    
    using Leadtools.Wia;
    
  8. Declare the following private variable:

    [Visual Basic]

    
    Private WithEvents session As WiaSession
    
    [C#]
    
    private WiaSession session;
    
  9. Add an event handler to the Form1 Load event and code it as follows:

    [Visual Basic]

    
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
       Try
          session = new WiaSession
          session.Startup(WiaVersion.Version1)
       Catch ex As Exception
          MessageBox.Show(ex.Message)
       End Try
    End Sub
    
    [C#]
    
    private void Form1_Load(object sender, System.EventArgs e)
    {
       try
       {
          session = new WiaSession();
          session.Startup(WiaVersion.Version1);
       }
       catch (Exception ex)
       {
          MessageBox.Show(this, ex.Message);
       }
    }
    
  10. Add an event handler to the Form1 Closing event and code it as follows:

    [Visual Basic]

    
    Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
       Try
          session.Shutdown()
       Catch ex As Exception
          MessageBox.Show(ex.Message)
       End Try
    End Sub   
    
    [C#]
    
    private void Form1_FormClosing(object sender, FormClosingEventArgs e)
    {
       try
       {
          session.Shutdown();
       }
       catch (Exception ex)
       {
          MessageBox.Show(this, ex.Message);
       }
    }
    
  11. Add an event handler to the session EnumDevicesEvent event and code it as follows:

    [Visual Basic]

    
    Private Sub session_EnumDevicesEvent(ByVal sender As Object, ByVal e As WiaEnumDevicesEventArgs) Handles session.EnumDevicesEvent
      Dim strMsg As String = String.Format("Device ID: {0}{1}Device Name: {2}{1}Device Description: {3}", e.DeviceID, Constants.vbLf, e.DeviceName, Constants.vbLf, e.DeviceDesc)
      MessageBox.Show(strMsg, "Available WIA Devices")
    End Sub
    
    [C#]
    
    private void session_EnumDevicesEvent(object sender, WiaEnumDevicesEventArgs e)
    {
      string strMsg = string.Format("Device ID: {0}\nDevice Name: {2}\nDevice Description: {3}", e.DeviceID, e.DeviceName, e.DeviceDesc);
      MessageBox.Show(strMsg, "Available WIA Devices");
    }
    
  12. Add an event handler to the btnEnumWiaDevices Click event and code it as follows:

    [Visual Basic]

    
    Private Sub btnEnumWiaDevices_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEnumWiaDevices.Click
       Try
          session.EnumDevices()
       Catch ex As Exception
          MessageBox.Show(ex.Message)
       End Try
    End Sub   
    
    [C#]
    
    private void btnEnumWiaDevices_Click(object sender, System.EventArgs e)
    {
       try
       {
          session.EnumDevicesEvent += new EventHandler<WiaEnumDevicesEventArgs>(session_EnumDevicesEvent);
          session.EnumDevices();
       }
       catch (Exception ex)
       {
          MessageBox.Show(this, ex.Message);
       }
    }
    
  13. Build, and Run the program to test it.