asked on

Rasing events vb.net

Converting a project from C# to VB.NET and having trouble coding the event handler.
Here is sample from C# and VB.NET Need to know how to enable the event handler in VB

public class RowControl
{
public delegate void AddNewRowEventHandler(object sender, EventArgs e);
public event AddNewRowEventHandler AddNewRowEvent;
...

on form: collectionslist

private void AddNewRow(int rowIDX)
{
RowControl control = new RowControl(ramCustomersDict, rowControlsList, rowIDX); //row 0 is column headers
control.stopLabel.Text = rowIDX.ToString();
rowControlsList.Add(control);
tableLayoutPanel1.Add(control);
control.AddNewRowEvent += new RowControl.AddNewRowEventHandler(this.AddNewRowEvent);
}

//***************************************************************************
private void AddNewRowEvent(object sender, EventArgs e)
{
RowControl rc = rowControlsList.Last();
if (rc.customerIdTextBox.Text.Length > 0 && rc.addressTextbox.Text.Length > 0)
{
int rowIDX = rowControlsList.Count + 1;
AddNewRow(rowIDX);
}
}

Now in VB, I have this:

Public Class RowControl
Public Delegate Sub AddNewRowEventHandler(sender As Object, e As EventArgs)
Public Event AddNewRowEvent As AddNewRowEventHandler
...

on the form:
Private Sub AddNewRow(rowIDX As Integer)
dim control as New RowControl(ramCustomersDict, rowControlsList, rowIDX)
'row 0 is column headers
control.stopLabel.Text = rowIDX.ToString()
rowControlsList.Add(control)
TableLayoutPanel1.Add(control)

control.AddNewRowEvent() += New RowControl.AddNewRowEventHandler(AddressOf Me.AddNewRowEvent)
End Sub

'***************************************************************************
Private Sub AddNewRowEvent(sender As Object, e As EventArgs)
Dim rc As RowControl = rowControlsList.Last
If rc.customerIdTextBox.Text.Length > 0 AndAlso rc.addressTextbox.Text.Length > 0 Then
Dim rowIDX As Integer = rowControlsList.Count + 1
AddNewRow(rowIDX)
End If
End Sub

SO my question is....How do I get my event raised?

I am getting the error saying i Need to call raiseevent, but when I try to enter the code for raiseevent, nothing appears.

Thanks

ASKER CERTIFIED SOLUTION

Kyle Abrahams, PMP

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it_saige

Using your above example, here is one way you could accomplish your task:

RowControl.vb -

Public Class RowControl
	Public Delegate Sub AddNewRowEventHandler(sender As Object, e As EventArgs)
	Private ReadOnly _addNewRowEventHandlers As List(Of AddNewRowEventHandler)
	Public Custom Event AddNewRowEvent As AddNewRowEventHandler
		AddHandler(ByVal value As PropertyChangedEventHandler)
			_addNewRowEventHandlers.Add(value)
		End AddHandler

		RemoveHandler(ByVal value As PropertyChangedEventHandler)
			_addNewRowEventHandlers.Remove(value)
		End RemoveHandler

		RaiseEvent(ByVal sender As Object, ByVal e As EventArgs)
			For Each handler As PropertyChangedEventHandler In _propertyChangedHandlers
				Try
					handler.Invoke(sender, e)
				Catch ex As Exception
					Debug.WriteLine(String.Format("Exception while invoking event handler: {0}", ex))
				End Try
			Next
		End RaiseEvent
	End Event

	Protected Overridable Sub OnNewRowAdded(ByVal sender As Object, ByVal e As EventArgs)
		RaiseEvent AddNewRowEvent(sender, e)
	End Sub 

	Private Sub SomeMethodUsedToAddARow(DataRow row)
		' Perform methods used to add a row
		' Ok now we fire our event.
		OnNewRowAdded(Me, New EventArgs())
	End Sub
End Class

Open in new window

Form methods -

Private Sub AddNewRow(rowIDX As Integer)
	Dim control as New RowControl(ramCustomersDict, rowControlsList, rowIDX)
	'row 0 is column headers
	control.stopLabel.Text = rowIDX.ToString()
	rowControlsList.Add(control)
	TableLayoutPanel1.Add(control)

	AddHandler control.AddNewRowEvent, AddressOf Me.AddNewRowEvent
End Sub

'***************************************************************************
Private Sub AddNewRowEvent(sender As Object, e As EventArgs)
	Dim rc As RowControl = rowControlsList.Last
	If rc.customerIdTextBox.Text.Length > 0 AndAlso rc.addressTextbox.Text.Length > 0 Then
		Dim rowIDX As Integer = rowControlsList.Count + 1
		AddNewRow(rowIDX)
	End If
End Sub

Open in new window

-saige-