How to set rich text format in cells in C++.NET

/*------------------------------------------------------------------
 | Tutorial 19
 |
 | This tutorial shows how to create an Excel file in C++.NET having
 | multiple sheets. The first sheet is filled with data and the
 | first cell of the second row contains data in rich text format.
 -------------------------------------------------------------------*/

#include <conio.h>
#include <stdio.h>

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

int main()
{
    Console::WriteLine("Tutorial 19\n----------\n");

    // Create an instance of the class that exports Excel files having two sheets
    ExcelDocument ^workbook = gcnew ExcelDocument(2);

    // Set the sheet names
    workbook->easy_getSheetAt(0)->setSheetName("First tab");
    workbook->easy_getSheetAt(1)->setSheetName("Second tab");

    // Get the table of data for the first worksheet
    ExcelWorksheet ^xlsFirstTab = safe_cast<ExcelWorksheet^>(workbook->easy_getSheetAt(0));
    ExcelTable ^xlsFirstTable = xlsFirstTab->easy_getExcelTable();

    // Create the string used to set the RTF in cell
    String ^sFormattedValue = "This is <b>bold</b>.";
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <i>italic</i>.");
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <u>underline</u>.");
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <underline double>double underline");
    sFormattedValue = String::Concat(sFormattedValue ,"</underline double>.");
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <font color=red>red</font>.");
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <font color=rgb(255,0,0)>red</font> too.");
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <font face=\"Arial Black\">Arial Black</font>.");
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <font size=15pt>size 15</font>.");
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <s>strikethrough</s>.");
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <sup>superscript</sup>.");
    sFormattedValue = String::Concat(sFormattedValue ,"\nThis is <sub>subscript</sub>.");
    sFormattedValue = String::Concat(sFormattedValue ,"\n<b>This</b> <i>is</i> ");
    sFormattedValue = String::Concat(sFormattedValue ,"<font color=red face=\"Arial Black\" size=15pt>");
    sFormattedValue = String::Concat(sFormattedValue ,"<underline double>formatted</underline double></font> ");
    sFormattedValue = String::Concat(sFormattedValue ,"<s>text</s>.");

    // Set the rich text value in cell
    xlsFirstTable->easy_getCell(1, 0)->setHTMLValue(sFormattedValue); 
    xlsFirstTable->easy_getCell(1, 0)->setDataType(DataType::STRING);
    xlsFirstTable->easy_getCell(1, 0)->setWrap(true); 
    xlsFirstTable->easy_getRowAt(1)->setHeight(250);
    xlsFirstTable->easy_getColumnAt(0)->setWidth(250);

    // Export Excel file
    Console::WriteLine("Writing file C:\\Samples\\Tutorial19 - RTF for Excel cells.xlsx.");
    workbook->easy_WriteXLSXFile("C:\\Samples\\Tutorial19 - RTF for Excel cells.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..."));

    // Dispose memory
    delete workbook;

    Console::ReadLine();

    return 0;
}