Excel进程拒绝关闭

Question

public static void GenerateExcel()
    {
        string conString = @"Server=DESKTOP-QVPUIDU\SQLEXPRESS; Database=Erasmus_Students;Integrated Security = SSPI;";
        StringBuilder query = new StringBuilder();
        query.Append("select * from ErasmusStudent");

        SQL.DataTable dtProducts = new SQL.DataTable();
        using (SqlConnection cn = new SqlConnection(conString))
        {
            using (SqlDataAdapter da = new SqlDataAdapter(query.ToString(), cn))
            {
                da.Fill(dtProducts);
            }
        }


        Excel._Workbook oWB;
        Excel._Worksheet oSheet;
        Excel.Application oXL;

        oXL = new Application();
        oWB = oXL.Workbooks.Add(Missing.Value);
        oSheet = (_Worksheet)oWB.ActiveSheet;
        oSheet = (_Worksheet)oXL.Worksheets.Add();
        oSheet.Name = "Erasmus";


        try
        {
            SQL.DataTable dtCategories = dtProducts.DefaultView.ToTable(true, "FirstName");

            foreach (SQL.DataRow category in dtCategories.Rows)
            {

                string[] colNames = new string[dtProducts.Columns.Count];

                int col = 0;

                foreach (SQL.DataColumn dc in dtProducts.Columns)
                    colNames[col++] = dc.ColumnName;
                string lastColumn = "A";
                if (dtProducts.Columns.Count > 25)
                    lastColumn += (char)(65 + dtProducts.Columns.Count - 1);                      
                else
                    lastColumn = Convert.ToString((char)(65 + dtProducts.Columns.Count - 1));

                oSheet.get_Range("A1", lastColumn + "1").Value2 = colNames;
                oSheet.get_Range("A1", lastColumn + "1").Font.Bold = true;
                oSheet.get_Range("A1", lastColumn + "1").VerticalAlignment = Excel.XlVAlign.xlVAlignCenter;

                SQL.DataRow[] dr = dtProducts.Select(string.Format("FirstName='{0}'", category[0].ToString()));

                string[,] rowData = new string[dr.Count<SQL.DataRow>(), dtProducts.Columns.Count];

                int rowCnt = 0;
                int redRows = 2;
                foreach (SQL.DataRow row in dr)
                {
                    for (col = 0; col < dtProducts.Columns.Count; col++)
                    {
                        rowData[rowCnt, col] = row[col].ToString();
                    }

                    /*if (int.Parse(row["ReorderLevel"].ToString()) < int.Parse(row["UnitsOnOrder"].ToString()))
                    {
                        Range range = oSheet.get_Range("A" + redRows.ToString(), "J" + redRows.ToString());
                        range.Cells.Interior.Color = System.Drawing.Color.Red;
                    } */
                    redRows++;
                    rowCnt++;
                }
                oSheet.get_Range("A2", lastColumn + rowCnt.ToString()).Value2 = rowData;
            }

            oXL.DisplayAlerts = false;
            oWB.SaveAs("Erasmus.xlsx");
            oWB.Close(0);
            oXL.Quit();
            SendEmail();



        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
        }
        finally
        {
            Marshal.ReleaseComObject(oSheet);
            Marshal.ReleaseComObject(oWB);
            Marshal.ReleaseComObject(oXL);
        }
    }

所以问题是，每次运行构建时，excel的一个进程都没有关闭，我用30-40个打开的进程完成了我的一天，现在我意识到了这一点。 我试图通过退出并关闭来关闭文件，并且我还试图与Marshal一起发布它，目前我没有想法。 欢迎任何建议/代码改进。

Open processes