Как вставить «--SELECT--» в поле со списком после привязки данных из таблицы данных в winform, используя c #

Question

OleDbCommand cmd = new OleDbCommand("SELECT  DISTINCT [DEPUTED BU] FROM [sheet1$] where [DEPUTED BU] is NOT NULL", oledbConn);
OleDbDataAdapter oleda = new OleDbDataAdapter();
oleda.SelectCommand = cmd;
DataSet ds = new DataSet();
oleda.Fill(ds, "Employees");
DataTable dt = ds.Tables["Employees"];
oledbConn.Open();
CombTBu.DataSource = dt;
CombTBu.DisplayMember = "DEPUTED BU";
CombTBu.ValueMember = "DEPUTED BU";
oledbConn.Close();
DataRow dr = dt.NewRow();
dt.Rows.InsertAt(dr, 0);
CombTBu.SelectedIndex = 0;

// я могу добавить пустую строку. Но как заполнить данные в добавленную новую строку ???Можете ли вы помочь мне плз ???

Answer 1

OleDbConnection oledbConn = new OleDbConnection(connString);
OleDbCommand cmd = new OleDbCommand("SELECT  DISTINCT [DEPUTED BU] FROM [sheet1$]", oledbConn);
OleDbDataAdapter oleda = new OleDbDataAdapter();
oleda.SelectCommand = cmd;
DataSet ds = new DataSet();
oleda.Fill(ds, "Employees");
DataTable dt = ds.Tables["Employees"];
oledbConn.Open();
CombTBu.DataSource = dt;
CombTBu.DisplayMember = "DEPUTED BU";
CombTBu.ValueMember = "DEPUTED BU";
DataRow drNewRow = dt.NewRow();
drNewRow["DEPUTED BU"] = "--Select--";
dt.Rows.InsertAt(drNewRow, 0);
CombTBu.SelectedIndex = 0;
oledbConn.Close();