C Sharp 非同期処理からUIスレッドにアクセスし画面を更新する

C# 非同期処理からUIスレッドにアクセスし画面を更新する

C Sharp |

例

public partial class MainForm : Form
{
 
    public MainForm()
    {
    }
 
    private async void btnHoge_Click(object sender, EventArgs e)
    {
        await CrawlGuppy();
    }
 
    private async Task CallBusyService()
    {
 
        IProgress<string> progress = new Progress<string>(msg =>
        {
            lblStatus.Text = $"処理中･･･{msg}";
        });
 
        await Task.Run(() =>
        {
            (new Service()).DoBusyTask(progress, "some parameter");
        });
    }
}
 
public class Service()
{
	public void DoBusyTask(IProgress<string> progress, string param)
	{
		progress.Report("Message");
	}
}
 

例

• Task と Invoke と Delegete を利用

public partial class Form1 : Form
{        
    public delegate void UpdateStatusHandler(string msg);
 
    public void UpdateStatus(string msg)
    {
        lblStatus.Text = msg;
    }
    
    public void DoAsyncTaskButton_Click()
    {
        Task task = Task.Factory.StartNew(() =>
        {
            while (true)
            {
                string msg = ""; // some messages
                lblStatus.Invoke(new UpdateStatusHandler(UpdateStatus), msg);
            }
        });
    }
}