Loading CSV file in C# Winform get's older version

Question

The program i got is able to load CSV and Excel files in to a datagridview. This works perfectly fine except the CSV files retain old data.

For example, the CSV file has 30 values. i load the data in to the datagridview and it works fine. I close the application and i then edit the CSV file removing 26 of the rows. The next time i open the application and load the file it still get's the version with 30 values even tho that file no longer exists.

To be clear, i open and edit the file in Notepad and it works as intended, but even after editing it in notepad my Winform application seems to load the previous version. Even if i rename the file it still takes the data that should no longer exist. Even after completely restarting the PC the file still retains data that should not exist. BUT! If i move the file to a different folder (add new folder and just throw it in there) it does load the new data...

EDIT: It seems that it is actually loading all CSV files in the folder. (including older versions)

what could cause this problem? Seeing the Excel files are not experiencing this problem.

The code used:

    private void OpenExcel()
    {
        OpenFileDialog openFileDialog1 = new OpenFileDialog
        {
            InitialDirectory = @"C:\",
            Title = "Browse Text Files",

            CheckFileExists = true,
            CheckPathExists = true,

            DefaultExt = "txt",
            FilterIndex = 2,
            RestoreDirectory = true,

            ReadOnlyChecked = true,
            ShowReadOnly = true,
            Filter = "Excel Worksheets|*.csv"
        };

        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            FileLocation  = openFileDialog1.FileName;                
            GetExcelSheetNames(openFileDialog1.FileName);

            MyConnection = new OleDbConnection(connString);

            MyCommand = new OleDbDataAdapter("select * from [" + SheetName + "]", MyConnection);
            MyCommand.TableMappings.Add("Table", "TestTable");
            Datatable_Temp = new DataTable();
            MyCommand.Fill(Datatable_Temp);
            MyConnection.Close();              
        }
        else
        {
            Canceled = true;
        }            
    }

    private string GetExcelSheetNames(string excelFile)
    {
        OleDbConnection objConn = null;
        DataTable dt = null;
        string CSVOrNot = excelFile.Substring(excelFile.Length - 3);    

        try
        {
            // Connection String.
            if (CSVOrNot == "csv")
            {
                connString = string.Format(@"Provider=Microsoft.Jet.OleDb.4.0; Data Source={0};Extended Properties=""Text;HDR=YES;FMT=Delimited""", Path.GetDirectoryName(excelFile));
            }
            else
            {
                connString = "Provider=Microsoft.ACE.OLEDB.12.0; Data Source=" + excelFile + ";Extended Properties=Excel 12.0;";
            }
            // Create connection object by using the preceding connection string.
            objConn = new OleDbConnection(connString);
            // Open connection with the database.
            objConn.Open();
            // Get the data table containg the schema guid.
            dt = objConn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);

            if (dt == null)
            {
                MessageBox.Show("No Data Found");
                return null;
            }
            SheetName = dt.Rows[0]["TABLE_NAME"].ToString();

            return SheetName;
        }
        catch
        {
            return null;
        }
        finally
        {
            // Clean up.
            if (objConn != null)
            {
                objConn.Close();
                objConn.Dispose();
            }
            if (dt != null)
            {
                dt.Dispose();
            }
        }
    }

Answer 1

i Found the issue, it was different then i thought. Seeing older versions of the file were also in the folder i didn't notice that it wasn't taking an older version of itself but it was simply merging all CSV files in to the output.

I searched for this instead and found the following post: c# reading csv file gives not a valid path

i added an if clause to see if the file is a csv file and then use the following: Because the difference between opening an Excel or a CSV file is is that the Excel file asked for path and file name while CSV only wants the path and later on a query to select the file...a bit odd but ok.

MyCommand = new OleDbDataAdapter("SELECT * FROM [" + Path.GetFileName(openFileDialog1.FileName) + "]", MyConnection);