EasyXLS

How to export DataSet to Excel in J#.NET

package Tutorial01;

/* -----------------------------------------------------------------------
 * Tutorial 01
 *
 * This code sample shows how to export DataSet to Excel file in J#.
 * The DataSet contains data from a SQL database, but it also can contain
 * data from other sources like GridView, DataGridView, DataGrid or other.
 * The cells are formatted using a predefined format.
 * -------------------------------------------------------------------- */

import System.Console;
import System.Data.*;
import EasyXLS.*;
import EasyXLS.Constants.*;

public class Tutorial01
{
    public Tutorial01()
    {
    }

    /** @attribute System.STAThread() */
    public static void main(String[] args)
    {
        Console.WriteLine("Tutorial 01\n-----------\n");

        // Create an instance of the class that exports Excel files
        ExcelDocument workbook = new ExcelDocument();

        // Create the database connection
        String sConnectionString = "Initial Catalog=Northwind;Data Source=localhost;Integrated Security=SSPI;";
        System.Data.SqlClient.SqlConnection sqlConnection = 
                              new System.Data.SqlClient.SqlConnection(sConnectionString);
        sqlConnection.Open();       

        // Create the adapter used to fill the dataset
        String sQueryString = "SELECT TOP 100 CAST(Month(ord.OrderDate) AS varchar) + " +
                              "'/' + CAST(Day(ord.OrderDate) AS varchar) + " + 
                              "'/' + CAST(year(ord.OrderDate) AS varchar) AS 'Order Date', "  +
                              "P.ProductName AS 'Product Name', O.UnitPrice AS Price, O.Quantity, "  +
                              "O.UnitPrice * O. Quantity AS Value " +
                              "FROM Orders AS ord, [Order Details] AS O, Products AS P "+
                              "WHERE O.ProductID = P.ProductID AND O.OrderID = ord.OrderID";
        System.Data.SqlClient.SqlDataAdapter adp = 
                              new System.Data.SqlClient.SqlDataAdapter(sQueryString, sqlConnection);

        // Populate the dataset
        DataSet dataset  = new DataSet();
        adp.Fill(dataset);

        // Export the Excel file
        Console.WriteLine("Writing file C:\\Samples\\Tutorial01 - export DataSet to Excel.xlsx.");
        workbook.easy_WriteXLSXFile_FromDataSet("C:\\Samples\\Tutorial01 - export DataSet to Excel.xlsx", dataset, 
                                                new ExcelAutoFormat(Styles.AUTOFORMAT_EASYXLS1), "Sheet1");

        // Confirm export of Excel file
        String sError = workbook.easy_getError();
        if (sError.Equals(""))
            Console.Write("\nFile successfully created. Press Enter to Exit...");
        else
            Console.Write("\nError encountered: " + sError + "\nPress Enter to Exit...");
         
        // Close the database connection
        sqlConnection.Close();

        // Dispose memory
        workbook.Dispose();
        dataset.Dispose();
        sqlConnection.Dispose();
        adp.Dispose();

        Console.ReadLine();
    }
}

EasyXLS Excel libraries:

.NET
Excel Library for J#
full .NET version to import, export or convert Excel files
Excel Writer for J#
.NET version to create and export Excel files
Express Excel Writer for J#
limited .NET version to create and export Excel files in predefined formats
Download EasyXLS™ Excel Library for J#

File formats:

MS Excel 97 - 2003
MS Excel 2007 - 2019
MS Excel 2021
Office 365
XLSXXLSMXLSBXLS
XMLHTMLCSVTXT