发布资源的 OpenFileDialog 问题

Question

我在 win 形式的 OpenFileDialog 中遇到了这个问题..

private void btnAllegato_Click(object sender, EventArgs e)
    {

        try
        {

            using (OpenFileDialog openFileDialog1 = new OpenFileDialog())
            {
                string path = string.Empty;

                openFileDialog1.Title = "Seleziona richiestaIT (PDF)..";
                openFileDialog1.Filter = ("PDF (.pdf)|*.pdf");
                openFileDialog1.FilterIndex = 1;
                openFileDialog1.FileName = "";


                if (openFileDialog1.ShowDialog() == DialogResult.OK)
                {

                    //salva l'intero path
                    path = openFileDialog1.FileName;

                    //nome file + estensione
                    string temp = openFileDialog1.SafeFileName;

                    //elimina l'estensione del file con IgnoreCase -> case Unsensitive
                    temp = Regex.Replace(temp, ".pdf", " ", RegexOptions.IgnoreCase);

                    //datatime + replace
                    string timenow = System.DateTime.Now.ToString();

                    //replace data da gg//mm/aaaa  ss:mm:hh  ----->  ad   gg-mm-aaaa_ss-mm-hh  
                    timenow = timenow.Replace(":", "-").Replace("/", "-");//.Replace(" ", " ");     

                    //effettua una copia dal path origine alla cartella nel NAS
                    _url = @"\\192.168.5.7\dati\SGI\GESTIONE IT\RichiesteIT\" + temp + timenow + ".pdf";

                    this.Cursor = Cursors.WaitCursor;

                    System.IO.File.Copy(path, _url);


                    this.Cursor = Cursors.Default;
                }


            }
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }

第一次运行...一切正常... 但是第二次点击 btn ...进程进入循环.. OpenFileDialog 是打开的，但完全是白色的...

我认为这是处置资源的问题..但我不知道如何解决它。

... ... @EDIT

经过几次尝试......我意识到问题出在我点击按钮后Inserisci>>。 第一次运行良好，但是当我在 btnInserisci 之后第二次点击 ... btnAllegato 时，我有循环过程。

代码 btnInserisci：

        private void btnInserisci_Click(object sender, EventArgs e)
    {
        try
        {
            if ((_IDRichiedente != -1) && (_data != string.Empty) && (_url != string.Empty))
            {
                //messageBox
                MessageBox.Show(_url);
                QueryAssist qa = new QueryAssist();
                string query = "INSERT INTO RICHIESTA_IT(ID_Risorsa, descrizione_richiesta, modulo_pdf, data_richiesta) VALUES('" + _IDRichiedente + "', '" + txtBreveDescrizione.Text + "', '" + _url + "', '" + _data + "');";
                MessageBox.Show(query);

                qa.runQuery(query);
                // qa.runQuery("INSERT INTO RICHIESTA_IT (ID_Risorsa, data_richiesta) VALUES ('" + _IDRichiedente + "','" + _data + "');");
            }
            else
            {
                MessageBox.Show("Selezionare il richiedente,data o allegato!");
            }
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }

    }

其中private int _IDRichiedente = -1; private string _data = String.Empty; private string _url = string.Empty; 是类的字段。

QueryAssist 是我创建连接、运行查询和断开连接的个人课程。 代码：

    class QueryAssist
{
    System.Data.OleDb.OleDbConnection _OleDBconnection;

    public QueryAssist()
    {
        this._OleDBconnection = null;
    }

    //riferimento di connessione al db
    private bool connectionDB()
    {
        string connection = "Provider=Microsoft.ACE.OLEDB.12.0; Data Source=\"\\\\192.168.5.7\\dati\\Scambio\\Sviluppo\\Impostazioni temporanea db Censimento\\CensimentoIT.accdb\"";
        try
        {
            _OleDBconnection = new System.Data.OleDb.OleDbConnection(connection);
            _OleDBconnection.Open();
            return true;

        }
        catch(Exception ex)
        {
            System.Windows.Forms.MessageBox.Show(ex.Message);
            return false;
        }
    }

    private void disconnectDB()
    {
        try
        {
            _OleDBconnection.Close();
        }
        catch (Exception ex)
        {
            System.Windows.Forms.MessageBox.Show(ex.Message);

        }
    }

    public System.Data.DataTable runQuery(string query)
    {
        try
        {
            if (connectionDB())
            {
                System.Data.DataTable dataTable = new System.Data.DataTable();
                System.Data.OleDb.OleDbCommand sqlQuery = new System.Data.OleDb.OleDbCommand(query, _OleDBconnection);
                System.Data.OleDb.OleDbDataAdapter adapter = new OleDbDataAdapter(sqlQuery);
                adapter.Fill(dataTable);
                disconnectDB();
                return dataTable;
            }
        }
        catch(Exception ex)
        {
            System.Windows.Forms.MessageBox.Show(ex.Message);
        }
        return null;

    }

    public int countRowsQueryResult(string query)
    {
        try
        {
            if (connectionDB())
            {
                System.Data.DataTable dataTable = new System.Data.DataTable();
                System.Data.OleDb.OleDbCommand sqlQuery = new System.Data.OleDb.OleDbCommand(query, _OleDBconnection);
                System.Data.OleDb.OleDbDataAdapter adapter = new OleDbDataAdapter(sqlQuery);
                adapter.Fill(dataTable);
                disconnectDB();
                return dataTable.Rows.Count;
            }
        }
        catch (Exception ex)
        {
            System.Windows.Forms.MessageBox.Show(ex.Message);
        }
        return -1;

    }
}

}

对不起我的英语

Answer 1

我认为 File.Copy 可能会挂起。尝试使用“c:\filename.pdf”之类的本地文件路径作为 URL 的相同代码。

//Crea il nome del file di destinazione
string _url = string.Format(@"c:\{0}{1}.pdf", temp, timenow);

如果此操作正常，则问题出在与 NAS 的连接上。

Answer 2

当您的应用程序不使用单线程单元 COM 模型时，通常会发现此问题。

通常，对于 WinForms，在 Program.cs 中的 Main 方法上，您需要有一个 [STAThread] 属性，例如：

[STAThread]
static void Main()
...

如果你没有那个，并且你确定你不需要 MTA，你可以在那里添加它。

否则，我有这个实用程序代码（我确定不是我写的，我只是从某个地方复制它，但不能真正给予信任，它在我的“winforms 实用程序类”中有一段时间了）普通对话框，它使用 STA 创建一个新线程并在那里调用对话框：

public class DialogInvoker
{
   public CommonDialog InvokeDialog;
   private Thread InvokeThread;
   private DialogResult InvokeResult;

   public DialogInvoker(CommonDialog dialog)
   {
      InvokeDialog = dialog;
      InvokeThread = new Thread(new ThreadStart(InvokeMethod));
      InvokeThread.SetApartmentState(ApartmentState.STA);
      InvokeResult = DialogResult.None;
   }

   public DialogResult Invoke()
   {
      InvokeThread.Start();
      InvokeThread.Join();
      return InvokeResult;
   }

   private void InvokeMethod()
   {
      InvokeResult = InvokeDialog.ShowDialog();
   }
}

要使用它，请更改：

if (openFileDialog1.ShowDialog() == DialogResult.OK) 

为：

if ((new DialogInvoker(openFileDialog1)).Invoke() == DialogResult.OK) 

Answer 3

将其从“使用”语句中删除。改变

using (OpenFileDialog openFileDialog1 = new OpenFileDialog())

到

OpenFileDialog openFileDialog1 = new OpenFileDialog();

看看这是否会有所作为。如果是这样，问题出在声明的处置上。

Answer 4

Io suggerirei di provare così：使用非 si utilizza con le 对话

try
{

    OpenFileDialog openFileDialog1 = new OpenFileDialog();
    string path = string.Empty;

    openFileDialog1.Title = "Seleziona richiestaIT (PDF)..";
    openFileDialog1.Filter = ("PDF (.pdf)|*.pdf");
    openFileDialog1.FilterIndex = 1;
    openFileDialog1.FileName = "";


    if (openFileDialog1.ShowDialog() == DialogResult.OK)
    {

        //salva l'intero path
        path = openFileDialog1.FileName;

        //Togli l'estensione dal file
        string temp = Path.GetFileNameWithoutExtension(openFileDialog1.FileName);

        //Crea un nome univoco usando data e ora
        string timenow = System.DateTime.Now.ToString("dd-MM-yyyy_ss-mm-hh");


        //Crea il nome del file di destinazione
        string _url = string.Format(@"\\192.168.5.7\dati\SGI\GESTIONE IT\RichiesteIT\{0}{1}.pdf", temp, timenow);

        this.Cursor = Cursors.WaitCursor;

        File.Copy(path, _url);


        this.Cursor = Cursors.Default;
    }
}
catch (Exception ex)
{
    MessageBox.Show(ex.Message);
}