cpp: read and write utf-8 text file using vs 2022

/*****************************************************************//**
 * \file   geovindu.h
 * \brief  业务操作方法
 *
 * \author geovindu,Geovin Du
 * \date   2023-04-22
***********************************************************************/
/**
 * https://learn.microsoft.com/zh-cn/cpp/build/reference/utf-8-set-source-and-executable-character-sets-to-utf-8?view=msvc-170
 *
 * .
 */
 
 
#pragma once
 
#define _UNICODE
 
#ifndef GEOVINDU_H
#define GEOVINDU_H
 
#include <iostream>
#include <windows.h>
#include<string>
#include<string.h>
#include<fstream>
#include<stdio.h>
#include<cstdlib>
#include<cstring>
#include<iomanip>
#include <iostream>
#include <windows.h>
 
 
namespace geovindu
{
 
    class Geovin
    {
 
    private:
 
    public:
 
 
        /// <summary>
        ///
        /// </summary>
        /// <param name="buffer"></param>
        /// <param name="len"></param>
        /// <returns></returns>
        //string to_utf8(const wchar_t* buffer, int len);
        /// <summary>
        ///
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        //string to_utf8(const wstring& str);
 
        /// <summary>
        ///
        /// </summary>
        /// <param name="str"></param>
        //void createFile(wstring& str);
        /// <summary>
        /// 写成UTF-8文本文件
        /// </summary>
        void createFile();
 
    };
 
};
 
 
#endif
#define UNICODE

#define _UNICODE
 
#include <iostream>
#include <windows.h>
#include<string>
#include<string.h>
#include<fstream>
#include<stdio.h>
#include<cstdlib>
#include<cstring>
#include<iomanip>
#include "geovindu.h"
 
 
using namespace std;
 
namespace geovindu
{
 
    /// <summary>
    ///
    /// </summary>
    /// <param name="buffer"></param>
    /// <param name="len"></param>
    /// <returns></returns>
    string to_utf8(const wchar_t* buffer, int len)
    {
        int nChars = ::WideCharToMultiByte(
            CP_UTF8,
            0,
            buffer,
            len,
            NULL,
            0,
            NULL,
            NULL);
        if (nChars == 0) return "";
        string newbuffer;
        newbuffer.resize(nChars);
        ::WideCharToMultiByte(
            CP_UTF8,
            0,
            buffer,
            len,
            const_cast<char*>(newbuffer.c_str()),
            nChars,
            NULL,
            NULL);
 
        return newbuffer;
    }
    /// <summary>
    ///
    /// </summary>
    /// <param name="str"></param>
    /// <returns></returns>
    string to_utf8(const wstring& str)
    {
        return to_utf8(str.c_str(), (int)str.size());
    }
    /// <summary>
    ///
    /// </summary>
    void createFile(wstring& strchinese)
    {
 
        ofstream testFile;
 
        testFile.open("demoinput.txt", std::ios::out | std::ios::binary);
 
        //std::wstring text = strchinese;          
 
        std::string outtext = to_utf8(strchinese);
 
        testFile << outtext;
 
        testFile.close();
 
    }
    ///<summary>
    /// 现有的文本写成UTF-8文本文件
    ///</summary>
    void Geovin::createFile()
    {
 
        ofstream testFile;
 
        testFile.open("geovindudemo.txt", std::ios::out | std::ios::binary);
 
        std::wstring text =
            L"涂聚文，你好，世界欢迎你！동생은 점수를 많이 땄어요\t geovindu\n Geovin Du \nНематериальное наследие водной рифмы\n"
            L"奇松・怪石・雲海と温泉\t大黄河を望む炳霊寺、驚異の張掖丹霞とシルクロードの要所9日間\n"
            L"Tours más solicitados\tParaíso en la Tierra - 13 Días\n"
            L"Entdecken Sie die schönsten Reiseziele von China mit unseren empfohlenen Touren.\n"
            L"Explorez les destinations les plus étonnantes de la Chine avec les visites recommandées.\n"
            L"\n";
 
        std::string outtext = to_utf8(text);
 
        testFile << outtext;
 
        testFile.close();
 
    }
 
};
 
#define UNICODE

// ConsoleTextFileDemoApp.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。
//geovindu Geovin Du
#define _UNICODE
#define _CRT_SECURE_NO_WARNINGS
 
 
#include <iostream>
#include <windows.h>
#include <string>
#include <string.h>
#include <fstream>
#include <stdio.h>
#include <cstdlib>
#include <cstring>
#include <iomanip>
#include <cstdio>
#include <codecvt>
#include <assert.h>
#include <windows.h>
#include <iostream>
#include <fstream>
#include <io.h>
#include <vector>
 
#include "ConvertEncode.h"
#include "geovindu.h"
#include "FileHelper.h"
 
 
using namespace std;
using namespace geovindu;
 
 
 
 
 
/// <summary>
/// 写成UTF-8文本文件
/// </summary>
void createFile(wstring& strchinese)
{
    ConvertEncode encode;
    wstring_convert<std::codecvt_utf8_utf16<wchar_t>, wchar_t> convert;
 
    ofstream testFile;
 
    testFile.open("geovinduinput.txt", std::ios::out | std::ios::binary);
 
    //std::wstring text = strchinese;
 
 
    std::string outtext = convert.to_bytes(strchinese);//
 
    testFile << outtext;
 
    testFile.close();
 
    std::string narrowStr = convert.to_bytes(strchinese);
    {
        std::ofstream ofs("geovinduinput2.txt");            //文件是utf8编码
        ofs << narrowStr;
    }
 
}
/// <summary>
/// 读文写文件 utf-8的文本文件
/// </summary>
void readfile()
{
    ConvertEncode encode;
    char sname[50];
    string stuID;//学号
    int num;//编号
    double english;//英语成绩
    double math;//数学成绩
    double cpp;//C++成绩
    vector<string> lines;
    string line;
    ifstream fin;
    fin.open("geovinduinput.txt", ios::in); //utf-8文件读
    if (!fin)
    {
        cout << "Fail to open the file!" << endl;
        exit(0);
    }
 
    //创建链表，并保存数据
    while (1)
    {
        if (!(fin >> sname >> stuID >> english >> math >> cpp))//从文件中读取数据 中文没有读出来
        {
            break;
        }
        else
        {
            cout << encode.UTF8ToGBDu(sname) << "\t" << stuID << "\t" << english << "\t" << math << "\t" << cpp << endl;
        }
    }
 
    while (getline(fin, line)) {
        lines.push_back(line);
    }
    fin.close();
    //cout << encode.UTF8ToGBDu(sname) << "\t" << stuID << "\t" << english << "\t" << math << "\t" << cpp << endl;
     
}
 
 
const int FBLOCK_MAX_BYTES = 256;
/*
// File Type.
typedef enum FileType
{
    ANSI = 0,
    unicode,
    UTF8,
}FILETYPE;
 
FILETYPE GetTextFileType(const std::string& strFileName);
 
int UnicodeToANSI(char* pDes, const wchar_t* pSrc);
*/
 
int main(void)
{
    std::cout << "Hello World! 涂聚文\n";
 
     
 
 
 
 
    /*代码无用
            FileHelper helper;
            // file test.
            std::string strFileANSI = "studentANSI.txt";
            std::string strFileUNICODE = "student.txt";
            std::string strFileUTF8 = "geovindudemo.txt";
 
            // please change the file name to test.
            std::string strFileName = strFileUTF8;
            //文件类型没有读对
            TEXTFILETYPE fileType = helper.GetTextFileType(strFileName);
 
            if (TextFileType_UNICODE == fileType)
            {
                wchar_t szBuf[FBLOCK_MAX_BYTES];
                memset(szBuf, 0, sizeof(wchar_t) * FBLOCK_MAX_BYTES);
 
                std::string strMessage;
 
                FILE* fp = NULL;
                fp = fopen(strFileName.c_str(), "rb");
                if (fp != NULL)
                {
                    // Unicode file should offset wchar_t bits(2 byte) from start.
                    fseek(fp, sizeof(wchar_t), 0);
                    while (fread(szBuf, sizeof(wchar_t), FBLOCK_MAX_BYTES, fp) > 0)
                    {
                        char szTemp[FBLOCK_MAX_BYTES] = { 0 };
 
                        helper.UnicodeToANSI(szTemp, szBuf);
                        strMessage += szTemp;
                        memset(szBuf, 0, sizeof(wchar_t) * FBLOCK_MAX_BYTES);
                    }
                }
                cout << "UNICODE" << endl;
                std::cout << strMessage << std::endl;
 
                fclose(fp);
            }
            else if (TextFileType_UTF8 == fileType)
            {
                char szBuf[FBLOCK_MAX_BYTES];
                memset(szBuf, 0, sizeof(char) * FBLOCK_MAX_BYTES);
 
                std::string strMessage;
 
                FILE* fp = NULL;
                fp = fopen(strFileName.c_str(), "rb");
                if (fp != NULL)
                {
                    // UTF-8 file should offset 3 byte from start position.
                    fseek(fp, sizeof(char) * 3, 0);
                    while (fread(szBuf, sizeof(char), FBLOCK_MAX_BYTES, fp) > 0)
                    {
                        strMessage += szBuf;
                        memset(szBuf, 0, sizeof(char) * FBLOCK_MAX_BYTES);
                    }
                }
                cout << "utf-8" << endl;
                std::cout << strMessage << std::endl;
 
                fclose(fp);
            }
            else
            {
                char szBuf[FBLOCK_MAX_BYTES];
                memset(szBuf, 0, sizeof(char) * FBLOCK_MAX_BYTES);
 
                std::string strMessage;
 
                FILE* fp = NULL;
                fp = fopen(strFileName.c_str(), "rb");
                if (fp != NULL)
                {
                    // common file do not offset.
                    while (fread(szBuf, sizeof(char), FBLOCK_MAX_BYTES, fp) > 0)
                    {
                        strMessage += szBuf;
                        memset(szBuf, 0, sizeof(char) * FBLOCK_MAX_BYTES);
                    }
                }
                cout << "ANSI" << endl;
                std::cout << strMessage << std::endl;
 
                fclose(fp);
 
 
            }
 
 
    */
 
 
 
 
    readfile();
    //读内容
    //std::wstring_convert<std::codecvt_utf8<wchar_t>> conv;
    //std::ifstream ifs(L"geovinduinput.txt");
    //while (!ifs.eof())
    //{
    //  string line;
    //  getline(ifs, line);
    //  wstring wb = conv.from_bytes(line);
    //  wcout.imbue(locale("chs"));         //更改区域设置 只为控制台输出显示 其他语言显示不了，中文可以
    //  wcout << wb << endl;
    //}
    //ifs.close();
 
 
    Geovin geovin;
    geovin.createFile();
    wstring allstr;
    wstring sname;
    wstring stuID;//学号
    int num;//编号
    double english;//英语成绩
    double math;//数学成绩
    double cpp;//C++成绩
    int location = 0;//位置编号
    int flag = 0;//标记是否有对应的编号
 
    wcout << "请输入新增学生的信息" << endl;
    wcout << "姓名\t" << "学号\t" << "英语\t" << "数学\t" << "C++\t" << endl;
    wcin.imbue(locale("chs"));//获取的是中文
    
    wcin >> sname >> stuID >> english >> math >> cpp;
 
    //allstr = sname + ' ' + stuID;
    allstr.append(sname); //C++ wstring::append
    allstr.append(L"\t");
    allstr.append(stuID);
    allstr.append(L"\t");
    allstr.append(to_wstring(english));
    allstr.append(L"\t");
    allstr.append(to_wstring(math));
    allstr.append(L"\t");
    allstr.append(to_wstring(cpp));
   // createFile(allstr);
 
 
    system("pause");
    return 0;
 
 
}
 
// 运行程序: Ctrl + F5 或调试 >“开始执行(不调试)”菜单
// 调试程序: F5 或调试 >“开始调试”菜单
 
// 入门使用技巧:
//   1. 使用解决方案资源管理器窗口添加/管理文件
//   2. 使用团队资源管理器窗口连接到源代码管理
//   3. 使用输出窗口查看生成输出和其他消息
//   4. 使用错误列表窗口查看错误
//   5. 转到“项目”>“添加新项”以创建新的代码文件，或转到“项目”>“添加现有项”以将现有代码文件添加到项目
//   6. 将来，若要再次打开此项目，请转到“文件”>“打开”>“项目”并选择 .sln 文件
 
 
 
 
 
#define UNICODE