所以，我的代码

if (System.IO.File.Exists(fileName))
        {
            System.IO.File.Delete(fileName);
        }
        SqlCeEngine en = new SqlCeEngine(connectionString);
        en.CreateDatabase();

        SqlCeConnection cn = new SqlCeConnection(connectionString);
        if (cn.State == ConnectionState.Closed)
            cn.Open();
        string sql = "create table EnergyMain(id int not null, date datetime not null, totalamount float)";
        SqlCeCommand cmd = new SqlCeCommand(sql, cn);
        cmd.ExecuteNonQuery();

        SqlCeCommand tbltodgv = new SqlCeCommand("EnergyMain", cn);
        tbltodgv.CommandType = CommandType.TableDirect;
        SqlCeResultSet rs = tbltodgv.ExecuteResultSet(ResultSetOptions.Scrollable | ResultSetOptions.Updatable);
        dgvMain.DataSource = rs;

        cn.Close();

Invalid attempt to call method Updatable when SqlResultSet is closed.

最佳答案

将datagridview绑定(bind)到结果集时，不要关闭底层连接，所以去掉cn.Close()

https://stackoverflow.com/questions/9887037/