Download Example

Simple download file example. Works with http, https, and ftp. If username and password are required add them to the client using System.Net.NetworkCredential(“username”, “password”).

Use the WebClient DownloadProgressChanged and DownloadFileCompleted events to display percent and start on finish action.

These examples will not work unless you create a winform to go along with them.

VB.net

Imports System.IO
Imports System.Net
Imports System.Threading
Imports System.Text

Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDownload.Click
        download(txtDownloadPath.Text.Trim, txtSavePath.Text.Trim)
    End Sub

    Private Shared percent As Integer = 0

    Public Sub Download(ByVal urlPath As String, ByVal savePath As String)
        Dim client As WebClient = New WebClient()
        'client.Credentials = New System.Net.NetworkCredential("username", "password")

        AddHandler client.DownloadProgressChanged, AddressOf ClientDownloadProgressChanged
        AddHandler client.DownloadFileCompleted, AddressOf ClientDownloadFileCompleted

        client.DownloadFileAsync(New Uri(urlPath), savePath)

    End Sub

    Private Sub ClientDownloadProgressChanged(ByVal sender As Object, ByVal e As DownloadProgressChangedEventArgs)

        Dim bytesIn As Double = Double.Parse(e.BytesReceived.ToString())
        Dim totalBytes As Double = Double.Parse(e.TotalBytesToReceive.ToString())
        Dim percentage As Double = bytesIn / totalBytes * 100

        ProgressBar1.Value = Integer.Parse(Math.Truncate(percentage).ToString())
        PaintProgressBarPercent(ProgressBar1)
    End Sub

    Private Sub ClientDownloadFileCompleted(ByVal sender As Object, ByVal e As EventArgs)
        'AsyncCompletedEventArgs
        MessageBox.Show("Download Completed")
    End Sub

    Private Sub PaintProgressBarPercent(ByRef a As ProgressBar)
        Dim percent As Integer = CInt(((CDbl((ProgressBar1.Value - ProgressBar1.Minimum)) / CDbl((ProgressBar1.Maximum - ProgressBar1.Minimum))) * 100))

        Using gr As Graphics = ProgressBar1.CreateGraphics()
            Dim p1 As New PointF(CType(a.Width / 2 - (gr.MeasureString(percent & "%", SystemFonts.DefaultFont).Width / 2.0F), Single), CType(a.Height / 2 - (gr.MeasureString(percent & "%", SystemFonts.DefaultFont).Height / 2.0F), Single))
            Try
                gr.DrawString(percent & "%", SystemFonts.DefaultFont, Brushes.Black, p1)
            Catch ex As Exception
            End Try

        End Using

    End Sub

End Class

C# Example

using System.IO;
using System.Net;
using System.Threading;
using System.Text;

public class Form1
{
    private void Button1_Click(System.Object sender, System.EventArgs e)
    {
        download(txtDownloadPath.Text.Trim, txtSavePath.Text.Trim);
    }
    
    private static int percent = 0;
    
    public void Download(string urlPath, string savePath)
    {
        WebClient client = new WebClient();
        //client.Credentials = New System.Net.NetworkCredential("username", "password")
        
        client.DownloadProgressChanged += ClientDownloadProgressChanged;
        client.DownloadFileCompleted += ClientDownloadFileCompleted;
        
            
        client.DownloadFileAsync(new Uri(urlPath), savePath);
    }
    
    
    private void ClientDownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
    {
        
        double bytesIn = double.Parse(e.BytesReceived.ToString());
        double totalBytes = double.Parse(e.TotalBytesToReceive.ToString());
        double percentage = bytesIn / totalBytes * 100;
        
        ProgressBar1.Value = int.Parse(Math.Truncate(percentage).ToString());
            
        PaintProgressBarPercent(ProgressBar1);
    }
    
    
    private void ClientDownloadFileCompleted(object sender, EventArgs e)
    {
        //AsyncCompletedEventArgs
        MessageBox.Show("Download Completed");
    }
    
    
    
    private void PaintProgressBarPercent(ref ProgressBar a)
    {
        int percent = (int)(((double)(ProgressBar1.Value - ProgressBar1.Minimum) / (double)(ProgressBar1.Maximum - ProgressBar1.Minimum)) * 100);
        
        using (Graphics gr = ProgressBar1.CreateGraphics()) {
            PointF p1 = new PointF((float)a.Width / 2 - (gr.MeasureString(percent + "%", SystemFonts.DefaultFont).Width / 2f), (float)a.Height / 2 - (gr.MeasureString(percent + "%", SystemFonts.DefaultFont).Height / 2f));
            try {
                gr.DrawString(percent + "%", SystemFonts.DefaultFont, Brushes.Black, p1);
            }
            catch (Exception ex) {
                
            }
            
        }
    }
}