public async void StartProcessingButton_Click(object sender, EventArgs e)
{
// The Progress<T> constructor captures our UI context,
// so the lambda will be run on the UI thread.
var progress = new Progress<int>(percent =>
{
textBox1.Text = percent + "%";
});
// DoProcessing is run on the thread pool.
await Task.Run(() => DoProcessing(progress));
textBox1.Text = "Done!";
}
public void DoProcessing(IProgress<int> progress)
{
for (int i = 0; i != 100; ++i)
{
Thread.Sleep(100); // CPU-bound work
if (progress != null)
progress.Report(i);
}
}
public async Task DownloadFileAsync(string fileName, IProgress<int> progress)
{
using (var fileStream = ...) // Open local file for writing
using (var ftpStream = ...) // Open FTP stream
{
while (true)
{
var bytesRead = await ftpStream.ReadAsync(...);
if (bytesRead == 0)
return;
await fileStream.WriteAsync(...);
if (progress != null)
progress.Report(bytesRead);
}
}
}
using System;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace ProgressBarDemo
{
public partial class Form3 : Form
{
public Form3()
{
InitializeComponent();
}
public void DoSomething(IProgress<int> progress)
{
for (int i = 1; i <= 100; i++)
{
Thread.Sleep(100);
if (progress != null)
progress.Report(i);
}
}
private async void btnStart_Click(object sender, EventArgs e)
{
progressBar1.Value = 0;
var progress = new Progress<int>(percent =>
{
progressBar1.Value = percent;
});
await Task.Run(() => DoSomething(progress));
}
}
}