c # как установить beginInvoke конец?

Question

У меня есть код моей системы для сохранения временного файла изображения в папку из pictureBox, затем я должен убедиться, что beginInvoke завершается, и код системы для удаления временного файла изображения из этой папки. Кто-нибудь знает, как это сделать?

Это мой код:

    //Image Selection End Point
    private void pictureBox1_MouseUp(object sender, MouseEventArgs e)
    {
        // Do nothing it we're not selecting an area.
        if (!RegionSelect) return;
        RegionSelect = false;

        //Display the original image.
        pictureBox1.Image = bmpImage;

        // Copy the selected part of the image.
        int wid = Math.Abs(x0 - x1);
        int hgt = Math.Abs(y0 - y1);
        if ((wid < 1) || (hgt < 1)) return;

        Bitmap area = new Bitmap(wid, hgt);
        using (Graphics g = Graphics.FromImage(area))
        {
            Rectangle source_rectangle = new Rectangle(Math.Min(x0, x1), Math.Min(y0, y1), wid, hgt);
            Rectangle dest_rectangle = new Rectangle(0, 0, wid, hgt);
            g.DrawImage(bmpImage, dest_rectangle, source_rectangle, GraphicsUnit.Pixel);
        }

        // Display the result.
        pictureBox3.Image = area;
        Bitmap bm = new Bitmap(area);
        bm.Save(@"C:\Users\Shen\Desktop\LenzOCR\TempFolder\tempPic.jpeg", System.Drawing.Imaging.ImageFormat.Jpeg);
        singleFileInfo = new FileInfo(@"C:\Users\Shen\Desktop\LenzOCR\TempFolder\tempPic.jpeg");
    }

    private void ScanBT_Click(object sender, EventArgs e)
    {
        var folder = @"C:\Users\Shen\Desktop\LenzOCR\LenzOCR\WindowsFormsApplication1\ImageFile";

        DirectoryInfo directoryInfo;
        FileInfo[] files;
        directoryInfo = new DirectoryInfo(folder);
        files = directoryInfo.GetFiles("*.jpg", SearchOption.AllDirectories);

        var processImagesDelegate = new ProcessImagesDelegate(ProcessImages2);
        processImagesDelegate.BeginInvoke(files, processImagesDelegate.EndInvoke, null);
    }

    private void ProcessImages2(FileInfo[] files)
    {
        var comparableImages = new List<ComparableImage>();

        var index = 0x0;

        var operationStartTime = DateTime.Now;

        foreach (var file in files)
        {
            if (exit)
            {
                return;
            }

            var comparableImage = new ComparableImage(file);
            comparableImages.Add(comparableImage);
            index++;
        }

        index = 0;

        similarityImagesSorted = new List<SimilarityImages>();

        operationStartTime = DateTime.Now;

        var fileImage = new ComparableImage(singleFileInfo);

        for (var i = 0; i < comparableImages.Count; i++)
        {
            if (exit)
                return;

            var destination = comparableImages[i];
            var similarity = fileImage.CalculateSimilarity(destination);
            var sim = new SimilarityImages(fileImage, destination, similarity);
            similarityImagesSorted.Add(sim);
            index++;
        }

        similarityImagesSorted.Sort();
        similarityImagesSorted.Reverse();
        similarityImages = new BindingList<SimilarityImages>(similarityImagesSorted);

        con = new System.Data.SqlClient.SqlConnection();
        con.ConnectionString = "Data Source=SHEN-PC\\SQLEXPRESS;Initial Catalog=CharacterImage;Integrated Security=True";
        con.Open();

        String getImage = "SELECT ImageName, ImagePath FROM CharacterImage WHERE ImageName='" + similarityImages[0].Destination.ToString() + "'";
        String getImage1 = "SELECT ImageName, ImagePath FROM CharacterImage WHERE ImageName='" + similarityImages[1].Destination.ToString() + "'";
        String getImage2 = "SELECT ImageName, ImagePath FROM CharacterImage WHERE ImageName='" + similarityImages[2].Destination.ToString() + "'";

        SqlCommand cmd = new SqlCommand(getImage, con);
        SqlDataReader rd = cmd.ExecuteReader();

        while (rd.Read())
        {
             getPath = rd["ImagePath"].ToString();
             pictureBox4.Image = Image.FromFile(getPath);
        }
        rd.Close();

        SqlCommand cmd1 = new SqlCommand(getImage1, con);
        SqlDataReader rd1 = cmd1.ExecuteReader();

        while (rd1.Read())
        {
            getPath1 = rd1["ImagePath"].ToString();
            pictureBox5.Image = Image.FromFile(getPath1);
        }
        rd1.Close();

        SqlCommand cmd2 = new SqlCommand(getImage2, con);
        SqlDataReader rd2 = cmd2.ExecuteReader();

        while (rd2.Read())
        {
            getPath2 = rd2["ImagePath"].ToString();
            pictureBox6.Image = Image.FromFile(getPath2);
        }
        con.Close();
     }

    private void pictureBox4_Click(object sender, EventArgs e)
    {
        if (pictureBox4.Image == null)
        {
            MessageBox.Show("Nothing has been scanned yet!", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
        }

        else
        {
            con = new System.Data.SqlClient.SqlConnection();
            con.ConnectionString = "Data Source=SHEN-PC\\SQLEXPRESS;Initial Catalog=CharacterImage;Integrated Security=True";
            con.Open();
            String getText = "SELECT ImagePath, Character FROM CharacterImage WHERE ImagePath='" + getPath + "'";
            SqlCommand cmd = new SqlCommand(getText, con);
            SqlDataReader rd = cmd.ExecuteReader();

            while (rd.Read())
            {
                for (int i = 0; i < 1; i++)
                {
                    String imageChar = rd["Character"].ToString();
                    Action showText = () => ocrTB.AppendText(imageChar);
                    ocrTB.Invoke(showText);
                }
            }
            rd.Close();
        }

    }

Answer 1

BeginInvoke возвращает вам IAsyncResult, который вы можете использовать для ожидания завершения операции:

IAsyncResult result = processImagesDelegate.BeginInvoke(files, processImagesDelegate.EndInvoke, null);

Затем вы можете проверить, завершена ли операция, используя свойство result.IsCompleted, или вы можете ждать на WaitHandle, возвращенном из result.AsyncWaitHandle.