[RESOLVED] [2.0] C# Class -> Howto RaiseEvent VB-like

[Dave Sell]

All,

Most of my work involves VB.*. I am familiar with defining a VB Class with a

Public Event thisEvent(args)

Now I am working with a C# Class, which is consumed by VB code. I need to make the C# Class "Raise an Event" which can be handled by the VB consumer code.

Here is a code snippet, of what I think I want to do:

namespace SNAPI_App
{
    public partial class mainForm : Form
    {

        MotoSnapi.SnapiScanner scanner1;
        MotoSnapi.SnapiScanner scanner2;

        int status = 0;                                      /* Return values of function calls */
        static short[] paramsList                            /* Parameter information list */
            = new short[SnapiDLL.MAX_PARAM_LEN];

        int selectedScanner = 0;
        static ArrayList scannerList = new ArrayList();

        public mainForm()
        {
            Public Event thisEvent; // <- this doesn't work...
            // ...

[Dave Sell]

OK I was able to find some sample code to help out, and I got it to work:

namespace SNAPI_App
{
    public partial class mainForm : Form
    {

        //declaring the event handler delegate
        public delegate void ButtonEventHandler(object source, int clickCount);
        //declaring the event
        public event ButtonEventHandler ButtonClick;
        //Function to trigger the event
        //This will be called when the user clicks the button
        public void clicked(int count)
        {
            if (ButtonClick != null) ButtonClick(this, count);
        }
        //
        public delegate void ScannerInput (object source, string strScanData);
        public event ScannerInput ScanData;
        public void scanned(string strInput)
        {
            if (ScanData != null) ScanData(this, strInput);
        }

        public mainForm()
        {

            InitializeComponent();

            // ...

Now, from VB-land:

Imports SNAPI_App
 
Public Class Form1
 
    Private WithEvents snapiApp As SNAPI_App.mainForm
 
    ' ...
 
    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        snapiApp = New SNAPI_App.mainForm
        snapiApp.Show()
        snapiApp.Visible = False
    End Sub
 
    Private Sub snapiApp_ScanData(ByVal source As Object, ByVal strScanData As String) Handles snapiApp.ScanData
        MsgBox(strScanData)
    End Sub