EasyXLS

How to export DataSet to Excel in C++.NET

/*------------------------------------------------------------------------
 | Tutorial 01
 |
 | This code sample shows how to export DataSet to Excel file in C++.NET
 | 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 (1).
 -------------------------------------------------------------------------*/
Click here to see the Excel file

#include "stdafx.h"

#using <System.Xml.dll>
#using <System.dll> 

using namespace System;
using namespace System::Data;
using namespace EasyXLS;
using namespace EasyXLS::Constants;

int main()
{
    Console::WriteLine("Tutorial 01\n----------\n");

    // Create an instance of the class that exports Excel files
    ExcelDocument ^workbook = gcnew ExcelDocument();
    
    // Create the database connection
    String ^sConnectionString = "Initial Catalog=Northwind;Data Source=localhost;Integrated Security=SSPI;";
    System::Data::SqlClient::SqlConnection ^sqlConnection = 
        gcnew 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) + ";
    sQueryString = String::Concat(sQueryString, "'/' + CAST(Day(ord.OrderDate) AS varchar) + ");
    sQueryString = String::Concat(sQueryString, "'/' + CAST(year(ord.OrderDate) AS varchar) AS 'Order Date', ");
    sQueryString = String::Concat(sQueryString, "P.ProductName AS 'Product Name', O.UnitPrice AS Price, ");
    sQueryString = String::Concat(sQueryString, "O.Quantity, O.UnitPrice * O. Quantity AS Value ");
    sQueryString = String::Concat(sQueryString, "FROM Orders AS ord, [Order Details] AS O, Products AS P ");
    sQueryString = String::Concat(sQueryString, "WHERE O.ProductID = P.ProductID AND O.OrderID = ord.OrderID");
    System::Data::SqlClient::SqlDataAdapter ^adp = 
        gcnew System::Data::SqlClient::SqlDataAdapter(sQueryString, sqlConnection);

    // Populate the dataset
    System::Data::DataSet ^ds  = gcnew System::Data::DataSet();
    adp->Fill(ds);

    // Export the Excel file (1)
    Console::WriteLine("Writing file C:\\Samples\\Tutorial01.xls.");
    workbook->easy_WriteXLSFile_FromDataSet("C:\\Samples\\Tutorial01.xls", ds, 
                                               gcnew 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(String::Concat("\nError encountered: ", sError, "\nPress Enter to Exit..."));
         
    // Close the database connection
    sqlConnection->Close();

    // Dispose memory
    delete workbook;
    delete ds;
    delete sqlConnection;
    delete adp;

    Console::ReadLine();

    return 0;
}


C++ without .NET Framework
This tutorial is valid for C++ applications that can use .NET Framework. For applications that does not have .NET Framework integrated, a similar code sample is available.

EasyXLS Excel libraries:

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

File formats:

MS Excel 97 - 2003
MS Excel 2007 - 2010
MS Excel 2013
MS Excel 2016
MS Excel 2019
XLSX XLSM XLSB XLS
XML HTML CSV TXT