read_xsl.txt

public DataTable ReadExcelContents(string fileName)
{
    try
    {
        OleDbConnection connection = new OleDbConnection();

        connection = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Extended Properties=Excel 8.0;Data Source=" + fileName); //Excel 97-2003, .xls
        //string excelQuery = @"Select [Day],[Outlook],[temp],[Humidity],[Wind], [PlaySport]
        //   FROM [Sheet1$]";

        string excelQuery = @"Select * FROM [Sheet1$]";
        connection.Open();
        OleDbCommand cmd = new OleDbCommand(excelQuery, connection);
        OleDbDataAdapter adapter = new OleDbDataAdapter();
        adapter.SelectCommand = cmd;
        DataSet ds = new DataSet();
        adapter.Fill(ds);
        DataTable dt = ds.Tables[0];


        dataGridView1.DataSource = dt.DefaultView;
        connection.Close();
        return dt;
    }
    catch (Exception ex)
    {
        MessageBox.Show("Program can't read file. " + ex.Message, "Please Note", MessageBoxButtons.OK, MessageBoxIcon.Error);
        return null;
    }
}
DataTable table = new DataTable();
OleDbConnection conn = new OleDbConnection();

OleDbCommand cmd = new OleDbCommand();
string path = @"E:\ICD101.xls";//duong dan toi file excel
string Strconn = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + path;
Strconn += ";Extended Properties=Excel 8.0";
conn.ConnectionString = Strconn;
cmd.CommandText = "Select * from [exceltmp$]";//ten sheet
cmd.Connection = conn;

cmd.Connection = conn;
OleDbDataAdapter dap = new OleDbDataAdapter(cmd);
dap.Fill(table);
dataGridView2.DataSource = table;

string strSqlconn1 = "Data Source =MAY15; Initial Catalog =temp; Integrated Security = True";
SqlConnection conn1 = new SqlConnection(strSqlconn1);
conn1.Open();
System.Data.SqlClient.SqlBulkCopy copy = new System.Data.SqlClient.SqlBulkCopy(conn1);
copy.DestinationTableName = "codedmchung";//ten table trong sql
copy.ColumnMappings.Add("Codedm", "CodeDM"); 
copy.ColumnMappings.Add("Ma_ICD", "Ma_ch");//tên c?t bên excel và tên c?t tuong ?ng trong sql 
copy.ColumnMappings.Add("Ten_ICD", "Ten_ch");

copy.WriteToServer(table);
copy.Close();
conn1.Close();
conn1.Dispose();