How to read XLSX file in C++

/* ------------------------------------------------------------------------------
 * Tutorial 36
 * 
 * This tutorial shows how to read an Excel XLSX file in C++ (the
 * XLSX file generated by Tutorial 04 as base template), modify
 * some data and save it to another XLSX file (Tutorial36 - read XLSX file.xlsx).
 * --------------------------------------------------------------------------- */

#include "EasyXLS.h"
#include <conio.h>

int main()
{
    printf("Tutorial 36\n----------\n");

    HRESULT hr;

    // Initialize COM
    hr = CoInitialize(0);

    // Use the SUCCEEDED macro and get a pointer to the interface
    if (SUCCEEDED(hr))
    {
        // Create a pointer to the interface that reads Excel files
        EasyXLS::IExcelDocumentPtr workbook;
        hr = CoCreateInstance(__uuidof(EasyXLS::ExcelDocument),
                              NULL,
                              CLSCTX_ALL,
                              __uuidof(EasyXLS::IExcelDocument),
                              (void**) &workbook) ;

        if (SUCCEEDED(hr)){

            // Read XLSX file
            printf("\nReading file: C:\\Samples\\Tutorial04.xlsx\n");
            if (workbook->easy_LoadXLSXFile("C:\\Samples\\Tutorial04.xlsx"))
            {
                // Get the table of data for the second worksheet
                EasyXLS::IExcelWorksheetPtr xlsSecondTab = 
                    (EasyXLS::IExcelWorksheetPtr)workbook->easy_getSheetAt(1);
                EasyXLS::IExcelTablePtr xlsTable = xlsSecondTab->easy_getExcelTable();

                // Write some data to the second sheet
                xlsTable->easy_getCell_2("A1")->setValue("Data added by Tutorial36");

                char* cellValue = (char*)malloc(11*sizeof(char));
                char* columnNumber = (char*)malloc(sizeof(char));
                for (int column=0; column<5; column++)
                {
                    strcpy_s(cellValue, 6, "Data ");
                    _itoa_s(column+ 1, columnNumber, 2, 10);
                    strcat_s(cellValue, 10, columnNumber);
                    xlsTable->easy_getCell(1, column)->setValue(cellValue);
                }

                // Export the new XLSX file
                printf("Writing file C:\\Samples\\Tutorial36 - read XLSX file.xlsx.");
                workbook->easy_WriteXLSXFile("C:\\Samples\\Tutorial36 - read XLSX file.xlsx");

                // Confirm export of Excel file
                _bstr_t sError = workbook->easy_getError();
                if (strcmp(sError, "") == 0){
                    printf("\nFile successfully created. Press Enter to Exit...");
                }
                else{
                    printf("\nError encountered: %s", (LPCSTR)sError);
                }
            }
            else
            {
                printf("\nError reading file C:\\Samples\\Tutorial04.xlsx %s\n",
                            (LPCSTR)((_bstr_t)workbook->easy_getError()));
            }

            // Dispose memory
            workbook->Dispose();
        }
        else{
            printf("Object is not available!");
        }
    }
    else{
        printf("COM can't be initialized!");
    }

    // Uninitialize COM
    CoUninitialize();

    _getch();
    return 0;
}

/*-------------------------------------------------------------------------------
 | Tutorial 36
 |
 | This tutorial shows how to read an Excel XLSX file in C++.NET (the
 | XLSX file generated by Tutorial 04 as base template), modify
 | some data and save it to another XLSX file (Tutorial36 - read XLSX file.xlsx).
 ------------------------------------------------------------------------------*/

using namespace System;
using namespace EasyXLS;
using namespace System::Data;
using namespace System::IO;

int main()
{
    Console::WriteLine("Tutorial 36\n----------\n");

    // Create an instance of the class that reads Excel files
    ExcelDocument ^workbook = gcnew ExcelDocument();

    // Read XLSX file
    Console::WriteLine("Reading file C:\\Samples\\Tutorial04.xlsx.\n");
    if (workbook->easy_LoadXLSXFile("C:\\Samples\\Tutorial04.xlsx"))
    {
        // Get the table of data for the second worksheet
        ExcelWorksheet ^xlsSecondTab = safe_cast<ExcelWorksheet^>(workbook->easy_getSheet("Second tab"));
        ExcelTable ^xlsSecondTable = xlsSecondTab->easy_getExcelTable();

        // Write some data to the second sheet
        xlsSecondTable->easy_getCell("A1")->setValue("Data added by Tutorial36");
        for (int column=0; column<5; column++)
        {
            xlsSecondTable->easy_getCell(1, column)->setValue(String::Concat("Data ", (column + 1).ToString()));
        }

        // Export the new XLSX file
        Console::WriteLine("Writing file C:\\Samples\\Tutorial36 - read XLSX file.xlsx.");
        workbook->easy_WriteXLSXFile("C:\\Samples\\Tutorial36 - read XLSX file.xlsx");

        // 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..."));
    }
    else
    {
        Console::WriteLine(String::Concat("\nError reading file C:\\Samples\\Tutorial04.xlsx \n", 
            workbook->easy_getError(), "\nPress Enter to Exit..."));
    }

    // Dispose memory
    delete workbook;

    Console::ReadLine();

    return 0;
}