使用 c# winform 更新数据网格中的数据以访问数据库文件

Question

我想更新数据网格数据以访问数据库，为数据库连接创建了单独的表，我想从更新按钮表单中的数据库类调用以更新访问数据库。

请在下面找到数据库连接代码和updatebutton表单代码我不知道如何在updatebutton表单中调用DBIO类方法

更新按钮表单代码

       namespace CatiaLicenseUsageReport
       {
          public partial class FrmCatiaLicenseUsageReport : Form
          {
            FileIO objFileIO ;
    Utilities objUtilities ;
    DBIO objDBIO ;

    private string logfilepath = "";
    private string DBPath = "";
    [This how i created the class for DBIO class][1]private void Initialize()
    {
        string logfilepath = ConfigurationManager.AppSettings.Get("LogFilePath");
        Logger.Init(logfilepath + "CatiaLicenseUsageReportTool.log");
        DBPath = ConfigurationManager.AppSettings.Get("DBFile");

        objFileIO = new FileIO();
        objUtilities = new Utilities();
        objDBIO = new DBIO();

    }
    DataTable dt = new DataTable();
    private void FrmCatiaLicenseUsageReport_Load(object sender, EventArgs e)
    {
        //Create Headers for the dataTable
        dt.Columns.Add("Department", typeof(string)).ReadOnly = true;
        dt.Columns.Add("AllottedLicense", typeof(int));

        LicenseAllctnGridView.DataSource = dt;

        //Add Rows details to the datatable
        dt.Rows.Add("AASI", 7);
        dt.Rows.Add("EAPS", 9);

        txtWeek.Enabled = false;
    
    }
    private void btnUpdtLicens_Click_1(object sender, EventArgs e)
    {
        var UpdateDB = objDBIO.UpdateLicenseUsageDataFromDG(DBPath);
     
         UpdateDB = (DataTable)LicenseAllctnGridView.DataSource;
        MessageBox.Show("Data Updated Successfully.");
    }
        

             namespace CatiaLicenseUsageReport.IO
            {
              public class DBIO
               {
             /// <summary>
             /// 
             /// </summary>
            /// <returns></returns>


    #region Read DataBase File Function
    /// 

    public DBIO()
    {
        _cnStr = string.Empty;
        _cmd = null;
        _cnn = null;
    }

    public void Reset()
    {
        _cnStr = string.Empty;
        _cmd = null;
        _cnn = null;
    }

    private string _cnStr;
    private OleDbCommand _cmd;
    private OleDbConnection _cnn;
    private OleDbDataAdapter _oda;

    /// <summary>
    /// Get Coonection for given file 
    /// </summary>
    /// <param name="fileName"></param>
    public bool GetConnectionToDb(string dbName)
    {
        try
        {
            _cmd = null;
            if (_cnn != null)
                _cnn.Close();
            _cnStr = GetConnectionString(dbName);

            _cnn = new OleDbConnection(_cnStr);
            _cnn.Open();

            return true;
        }
        catch (OutOfMemoryException)
        {
            return false;
        }
        catch (Exception)
        {
            return false;
        }
    }

    private string GetConnectionString(string dbName)
    {
        string cnnStr;
        string provider;

        provider = "Microsoft.Jet.OLEDB.4.0";

        cnnStr = "Provider=" + provider + ";Data Source=" + dbName + ";";
        
        return cnnStr;
    }

    public DataTable ImportLicenseUsageDataFromDB(string dbName)
    {
        string query;
        DataTable resultDt = new DataTable();
        try
        {
            GetConnectionToDb(dbName);
            //Retrive Data
            _oda = new OleDbDataAdapter();
            query = String.Format("select Department,AllottedLicense from AllottedLicense");
            _cmd = new OleDbCommand(query, _cnn);
            _oda.SelectCommand = _cmd;
            _oda.Fill(resultDt);

        }
        catch (Exception ex)
        {
            Console.WriteLine("Error in function ImportLicenseUsageDataFromDB" + ex.StackTrace);
            Logger.OutLine("Error in function ImportLicenseUsageDataFromDB" + ex.StackTrace);
            throw ex;

        }
        finally
        {
            _cmd = null;
            if (_cnn != null)
                _cnn.Close();
            //cnn = null;
        }
        return resultDt;
    }
    public DataTable UpdateLicenseUsageDataFromDG(string dbName)
    {
        string query;
        DataTable resultDt = new DataTable();
        try
        {               
            // _cnn.Open();
            GetConnectionToDb(dbName);
            query = String.Format("select Department,AllottedLicense from AllottedLicense");
            _cmd = new OleDbCommand(query, _cnn);
            //Retrive Data
            _cmd.ExecuteNonQuery();
            _oda = new OleDbDataAdapter(_cmd);
            _oda.Update(resultDt);
            //_oda.UpdateCommand = _cnn.CreateCommand();
            //_oda.UpdateCommand.CommandText = query;
            
            //if(_oda.UpdateCommand.ExecuteNonQuery()>0)
            //{
            //    _oda.SelectCommand = _cmd;
            //    _oda.Update(resultDt);      
            //}
            //query = String.Format("select Department,AllottedLicense from AllottedLicense");
            //_cmd = new OleDbCommand(query, _cnn);
            //_oda.SelectCommand = _cmd;
            //_oda.Fill(resultDt);

        }
        catch (Exception ex)
        {
            Console.WriteLine("Error in function ImportLicenseUsageDataFromDB" + ex.StackTrace);
            Logger.OutLine("Error in function ImportLicenseUsageDataFromDB" + ex.StackTrace);
            throw ex;

        }
        finally
        {
            _cmd = null;
            if (_cnn != null)
                _cnn.Close();
            //cnn = null;
        }
        return resultDt;
    }