Hinzufügen zu OLE-Typ Tabelle von DataTable C#

Question

Ich versuche, Daten zu einer Access-Tabelle mit der Auflistung DataRows von einem DataTable-Objekt hinzufügen, und in der Viewer eine gute Menge von Datensätzen (43), aber es füllt den gleichen Datensatz 43 mal. Setze ich meine Parameter falsch oder was mache ich falsch?

private void PopulateDB(DataTable dtDB) 
    { 
     lblDataStatus.Text = "populating master table..."; 
     this.Refresh(); 
     progressBar1.Visible = true; 
     progressBar1.Value = 1; 
     progressBar1.Maximum = dtDB.Rows.Count; 
     string strConn = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=\\path\fname.accdb"; 
     using (OleDbConnection conn = new OleDbConnection (strConn)) 
     { 
      using (OleDbCommand cmd = new OleDbCommand()) 
      { 
       foreach (DataRow dr in dtDB .Rows) 
       { 
        progressBar1.PerformStep(); 
       try 
       { 
        cmd.CommandText = "INSERT INTO PMADocMaster(PN, PNNewRev, PN8Digit, ECO, Mon, SupNum, URL) VALUES (?,?,?,?,?,?,?)"; 
        cmd.Parameters.Add("@pn", OleDbType.VarChar).Value = dr.Field<string>("PNFullNum"); 
        cmd.Parameters.Add("@rev", OleDbType.VarChar).Value = dr.Field<string>("PNNewRev"); 
        cmd.Parameters.Add("@pn8", OleDbType.VarChar).Value = dr.Field<string>("PN8Dig"); 
        cmd.Parameters.Add("@eco", OleDbType.VarChar).Value = dr.Field<string>("ECO"); 
        cmd.Parameters.Add("@mon", OleDbType.VarChar).Value = dr.Field<string>("Mon"); 
        cmd.Parameters.Add("@supnum", OleDbType.VarChar).Value = dr.Field<string>("SupNum"); 
        cmd.Parameters.Add("@url", OleDbType.VarChar).Value = dr.Field<string>("URL"); 
        cmd.Connection = conn; 
        conn.Open(); 
        cmd.ExecuteNonQuery(); 
        conn.Close(); 
       } 
       catch (Exception e) 
       { 
        MessageBox.Show("Error: " + e.Message); 
        lblDataStatus.Text = e.Message; 
        return; 
        // duplicates are happening, will check veracity of data afterwards 
       } 
       } 
       progressBar1.Visible = false; 
      } 
     } 
    } 

Answer 1

können Sie verwenden cmd.Parameters.clear() oder den Code zu optimieren, wie unten ..

private void PopulateDB(DataTable dtDB) 
    { 
     lblDataStatus.Text = "populating master table..."; 
     this.Refresh(); 
     progressBar1.Visible = true; 
     progressBar1.Value = 1; 
     progressBar1.Maximum = dtDB.Rows.Count; 
     string strConn = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=\\path\fname.accdb"; 
     using (OleDbConnection conn = new OleDbConnection(strConn)) 
     { 
      using (OleDbCommand cmd = new OleDbCommand("INSERT INTO PMADocMaster(PN, PNNewRev, PN8Digit, ECO, Mon, SupNum, URL) VALUES (?,?,?,?,?,?,?)",conn)) 
      { 
       try 
       { 
        cmd.Parameters.Add("@pn");, OleDbType.VarChar); 
        cmd.Parameters.Add("@rev", OleDbType.VarChar); 
        cmd.Parameters.Add("@pn8", OleDbType.VarChar); 
        cmd.Parameters.Add("@eco", OleDbType.VarChar); 
        cmd.Parameters.Add("@mon", OleDbType.VarChar); 
        cmd.Parameters.Add("@supnum", OleDbType.VarChar); 
        cmd.Parameters.Add("@url", OleDbType.VarChar); 
        conn.Open(); 
        foreach (DataRow dr in dtDB.Rows) 
        { 
         progressBar1.PerformStep(); 

         cmd.Parameters["@pn"].Value = dr.Field<string>("PNFullNum"); 
         cmd.Parameters["@rev"].Value = dr.Field<string>("PNNewRev"); 
         cmd.Parameters["@pn8"].Value = dr.Field<string>("PN8Dig"); 
         cmd.Parameters["@eco"].Value = dr.Field<string>("ECO"); 
         cmd.Parameters["@mon"].Value = dr.Field<string>("Mon"); 
         cmd.Parameters["@supnum"].Value = dr.Field<string>("SupNum"); 
         cmd.Parameters["@url"].Value = dr.Field<string>("URL"); 
         cmd.ExecuteNonQuery(); 
        } 

        conn.Close(); 
       } 
       catch (Exception e) 
       { 
        MessageBox.Show("Error: " + e.Message); 
        lblDataStatus.Text = e.Message; 
        return; 
        // duplicates are happening, will check veracity of data afterwards 
       } 
       progressBar1.Visible = false; 
      } 
     } 
    }