OleDbConnection conn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=3d.accdb");
            OleDbDataAdapter oda = new OleDbDataAdapter("select * from 3d", conn);
            DataSet ds = new DataSet();
            oda.Fill(ds);
            dataGridView1.DataSource = ds.Tables[0];  

感谢各位,我自己给解决了哈...