I have written a DLL in C#, and I would like to get callback from an event.
In C# I dit it the following way:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO;
using SevenZipControl;
namespace Utlility
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
Zipper.ProgressEvent += ProgressChanged;
}
delegate void ProgressChangedCallback(int value);
private void ProgressChanged(object sender, ProgressChangedEventArgs e)
{
SetProgressBarValue(e.ProgressPercentage);
}
private void SetProgressBarValue(int progress)
{
if (this.progressBar1.InvokeRequired)
{
ProgressChangedCallback d = new ProgressChangedCallback(SetProgressBarValue);
this.Invoke(d, new object[] { progress });
return;
}
progressBar1.Value = progress;
}
I tried the same in VB.NET, but the IDE already complains about my AddHandler approach:
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Text
Imports System.Windows.Forms
Imports System.IO
Imports SevenZipControl
Public Class Form1
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
AddHandler Zipper.ProgressEvent, AddressOf ProgressChanged(Zipper, ProgressChangedEventArgs)
End Sub
Private Sub ProgressChanged(sender As Object, e As ProgressChangedEventArgs)
SetProgressBarValue(e.ProgressPercentage)
End Sub
Private Sub SetProgressBarValue(progress As Integer)
ProgressBar1.Value = progress
End Sub
End Class
The C# implementation works fine, but in VB.NET, the IDE tells me that "Zipper" and "ProgressChangedEventArgs" are a type and cannot be used as an expression.
Can somebody tell me what I am doing wrong here? Also, it tells me that
The solution was much more difficult. I had to create an impromptou function:
Zipper.Compress(uPathIn, uPathOut, Function(l1, l2)
SetProgressBarValue(0)
End Function)
I am not sure if that is the cleanest solution, and the compiler warns me that the function Function (l1, l2) may not have a valid return value, but it does everything I wanted.