I want to show progress of calculations, which are performing in external library.
For example if I have some calculate method, and I want to use it for 100000 values in my Form class I can write:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Caluculate(int i)
{
double pow = Math.Pow(i, i);
}
private void button1_Click(object sender, EventArgs e)
{
progressBar1.Maximum = 100000;
progressBar1.Step = 1;
for(int j = 0; j < 100000; j++)
{
Caluculate(j);
progressBar1.PerformStep();
}
}
}
I should perform step after each calculation. But what if I perform all 100000 calculations in external method. When should I "perform step" if I don't want to make this method dependant on progress bar? I can, for example, write
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void CaluculateAll(System.Windows.Forms.ProgressBar progressBar)
{
progressBar.Maximum = 100000;
progressBar.Step = 1;
for(int j = 0; j < 100000; j++)
{
double pow = Math.Pow(j, j); //Calculation
progressBar.PerformStep();
}
}
private void button1_Click(object sender, EventArgs e)
{
CaluculateAll(progressBar1);
}
}
but I don't want to do like that.
This question is related to
c#
winforms
progress-bar
Since .NET 4.5 you can use combination of async and await with Progress for sending updates to UI thread:
private void Calculate(int i)
{
double pow = Math.Pow(i, i);
}
public void DoWork(IProgress<int> progress)
{
// This method is executed in the context of
// another thread (different than the main UI thread),
// so use only thread-safe code
for (int j = 0; j < 100000; j++)
{
Calculate(j);
// Use progress to notify UI thread that progress has
// changed
if (progress != null)
progress.Report((j + 1) * 100 / 100000);
}
}
private async void button1_Click(object sender, EventArgs e)
{
progressBar1.Maximum = 100;
progressBar1.Step = 1;
var progress = new Progress<int>(v =>
{
// This lambda is executed in context of UI thread,
// so it can safely update form controls
progressBar1.Value = v;
});
// Run operation in another thread
await Task.Run(() => DoWork(progress));
// TODO: Do something after all calculations
}
Tasks are currently the preferred way to implement what BackgroundWorker
does.
Tasks and
Progress
are explained in more detail here:
Hey there's a useful tutorial on Dot Net pearls: http://www.dotnetperls.com/progressbar
In agreement with Peter, you need to use some amount of threading or the program will just hang, somewhat defeating the purpose.
Example that uses ProgressBar and BackgroundWorker: C#
using System.ComponentModel;
using System.Threading;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, System.EventArgs e)
{
// Start the BackgroundWorker.
backgroundWorker1.RunWorkerAsync();
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
for (int i = 1; i <= 100; i++)
{
// Wait 100 milliseconds.
Thread.Sleep(100);
// Report progress.
backgroundWorker1.ReportProgress(i);
}
}
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
// Change the value of the ProgressBar to the BackgroundWorker progress.
progressBar1.Value = e.ProgressPercentage;
// Set the text.
this.Text = e.ProgressPercentage.ToString();
}
}
} //closing here
There is Task
exists, It is unnesscery using BackgroundWorker
, Task
is more simple. for example:
ProgressDialog.cs:
public partial class ProgressDialog : Form
{
public System.Windows.Forms.ProgressBar Progressbar { get { return this.progressBar1; } }
public ProgressDialog()
{
InitializeComponent();
}
public void RunAsync(Action action)
{
Task.Run(action);
}
}
Done! Then you can reuse ProgressDialog anywhere:
var progressDialog = new ProgressDialog();
progressDialog.Progressbar.Value = 0;
progressDialog.Progressbar.Maximum = 100;
progressDialog.RunAsync(() =>
{
for (int i = 0; i < 100; i++)
{
Thread.Sleep(1000)
this.progressDialog.Progressbar.BeginInvoke((MethodInvoker)(() => {
this.progressDialog.Progressbar.Value += 1;
}));
}
});
progressDialog.ShowDialog();
Source: Stackoverflow.com