gistfile1.cs

// Connection String to Excel Workbook
string excelConnectionString = @"Provider=Microsoft
    .Jet.OLEDB.4.0;Data Source=Book1.xls;Extended
    Properties=""Excel 8.0;HDR=YES;""";

// Create Connection to Excel Workbook
using (OleDbConnection connection =
             new OleDbConnection(excelConnectionString))
{
    OleDbCommand command = new OleDbCommand
            ("Select ID,Data FROM [Data$]", connection);

    connection.Open();
    
    // Create DbDataReader to Data Worksheet
    using (DbDataReader dr = command.ExecuteReader())
    {
        // SQL Server Connection String
        string sqlConnectionString = "Data Source=.;
           Initial Catalog=Test;Integrated Security=True";

        // Bulk Copy to SQL Server
        using (SqlBulkCopy bulkCopy =
                   new SqlBulkCopy(sqlConnectionString))
        {
            bulkCopy.DestinationTableName = "ExcelData";
            bulkCopy.WriteToServer(dr);
        }
    }
}