public OleDbDataAdapter FindForMdb(string mdbpath,string sql)
        {
            string connstr = "Provider = Microsoft.Jet.OLEDB.4.0; Data Source =" + mdbpath;
            OleDbConnection conn = new OleDbConnection(connstr);
            return new OleDbDataAdapter(sql, conn);
        }
private void btnFind_Click(object sender, EventArgs e)
        {
            string sql = txtFind.Text;
            int dataCount = GetMDBCount();
            OleDbDataAdapter da;
            System.Data.DataTable dt = new System.Data.DataTable();
            for (int i = 1; i < dataCount; i++)
            {
                string path = System.Windows.Forms.Application.StartupPath + "\\data" + i.ToString() + ".mdb";
                da=FindForMdb(path, sql);
                da.Fill(dt);
            }
            dataGridView1.DataSource = dt;
        }

for循环这里会出现从多个文件从的查找结果 ，怎么显示到窗体上?

   public static DataTable Uion(DataTable dt1,DataTable dt2)
        {
            DataRow addRow;
            foreach(DataRow row in dt2.Rows)
            {
                addRow = dt1.NewRow();
                for (int i = 0; i < dt1.Columns.Count; i++)
                {
                    addRow[i] = row[i];
                }
                dt1.Rows.Add(addRow);
            }
            return dt1;
        }
dt1与dt2字段数量与名称应该相同