Question

我有一个将图像保存到数据库的按钮，一个删除目录的功能是我在保存到数据库之前临时存储图像。
这是代码

private void btnSave_Click(object sender, EventArgs e)
    {
        imgTemp = new System.Windows.Forms.PictureBox();
        imgTemp.Image = Image.FromFile(@cwd + "\\Final.jpg");
        MemoryStream mstr = new MemoryStream();
        imgTemp.Image.Save(mstr, imgTemp.Image.RawFormat);
        byte[] arrImage = mstr.GetBuffer();
        //Set insert query
        imgTemp.Image = null; 
        imgTemp.Dispose();

        string qry = "insert into FinalImages (FinalImageName, FinalImage, Parts) values(@FinalImageName, @FinalImage, @Parts)";

        SqlConnection c = new SqlConnection(c_string);
        //Initialize SqlCommand object for insert.
        SqlCommand SqlCom = new SqlCommand(qry, c);

        //We are passing Original Image Path and Image byte data as sql parameters.
        SqlCom.Parameters.Add(new SqlParameter("@FinalImageName", SqlDbType.Char, 40)).Value = textBox1.Text + ".jpg";
        SqlCom.Parameters.Add(new SqlParameter("@FinalImage", SqlDbType.Image)).Value = arrImage;
        SqlCom.Parameters.Add(new SqlParameter("@Parts", SqlDbType.VarChar, 40)).Value = NumOfFiles;

        try
        {
            c.Open();
            SqlCom.ExecuteNonQuery();
        }
        catch (System.Data.SqlClient.SqlException err)
        {
            MessageBox.Show(err.Message);
        }
        finally
        {
            c.Close();
        }

        // How many Picture files in this folder
        imgArray2 = new System.Windows.Forms.PictureBox[NumOfFiles];
        for (int i = 0; i < NumOfFiles; i++)
        {
Bitmap(imgName[i]);
            imgArray2[i] = new System.Windows.Forms.PictureBox();
            imgArray2[i].Image = Image.FromFile(imgName[i]);
            string name2 = textBox1.Text + ".jpg";
            string name3 = imgName[i].Substring(imgName[i].LastIndexOf(@"\") + 1,           imgName[i].Length - imgName[i].LastIndexOf(@"\") - 1);
            MemoryStream mstr2 = new MemoryStream();
            imgArray2[i].Image.Save(mstr2, imgArray2[i].Image.RawFormat);
            byte[] arrImage2 = mstr2.GetBuffer();
            string cmd2 = "insert into ImageParts (FinalImageName, ImagePartName, ImagePart) values (@FIName2, @IPName, @IP)";

            SqlConnection c2 = new SqlConnection(c_string);
            SqlCommand comm2 = new SqlCommand(cmd2, c2);
            comm2.Parameters.Add(new SqlParameter("@FIName2", SqlDbType.Char, 40)).Value = name2;
            comm2.Parameters.Add(new SqlParameter("@IPName", SqlDbType.Char, 40)).Value = name3;
            comm2.Parameters.Add(new SqlParameter("@IP", SqlDbType.Image)).Value = arrImage2;

            try
            {
                c2.Open();
                comm2.ExecuteNonQuery();
            }
            catch (System.Data.SqlClient.SqlException err)
            {
                MessageBox.Show(err.Message);
            }
            finally
            {
                c2.Close();
            }

        }
        DelDir();
        this.Hide();
        fourthForm.Show();
    }

    private void DelDir()
    {
        string[] files = Directory.GetFiles(cwd);
        string[] dirs = Directory.GetDirectories(cwd);

        foreach (string file in files)
        {
            File.SetAttributes(cwd, FileAttributes.Normal);
            File.Delete(file);
        }

        Directory.Delete(cwd, false);
    }

这是完整的例外

A first chance exception of type 'System.IO.IOException' occurred in mscorlib.dll
System.IO.IOException: The process cannot access the file 'C:\...\Final.jpg' because it is being used by another process.
at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.File.Delete(String path)
at BlueStitch.frmStitch.DelDir() in C:\...\frmStitch.cs:line 953
at BlueStitch.frmStitch.button1_Click(Object sender, EventArgs e) in C:\...\frmStitch.cs:line 940
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ButtonBase.WndProc(Message& m)
at System.Windows.Forms.Button.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at BlueStitch.Program.Main() in C:\Users\Freddie Rosillo\Documents\Visual Studio 2008\Projects\BlueStitch\BlueStitch\BlueStitch\Program.cs:line 21

行是File.Delete(file);
我想我试图处理图像文件，但仍然无法工作
请帮忙

Answer 1

看看这两行：

imgTemp.Image = null;  
imgTemp.Dispose();

在您处置PictureBox之前，您正在释放对图像的引用。这意味着PictureBox 在调用Dispose（）方法时无法处理图像。在垃圾收集器调用图像的终结器之前，图像不会被处理。

Answer 2

我对此并不乐观，但我注意到你在第一部分处理你的形象非常小心：

    imgTemp.Image = null; 
    imgTemp.Dispose();

但你在第二部分忽略了这一点：

        imgArray2[i].Image = Image.FromFile(imgName[i]);
        string name2 = textBox1.Text + ".jpg";
        string name3 = imgName[i].Substring(imgName[i].LastIndexOf(@"\") + 1,           imgName[i].Length - imgName[i].LastIndexOf(@"\") - 1);
        MemoryStream mstr2 = new MemoryStream();
        imgArray2[i].Image.Save(mstr2, imgArray2[i].Image.RawFormat);
        byte[] arrImage2 = mstr2.GetBuffer();

尝试将这些添加到最后一部分的行中：

    //Set insert query
    imgArray2[i].Image = null; 
    imgArray2[i].Dispose();

System.IO.IOException：进程无法访问该文件

2 个答案: