텍스트 에디터 (GetOpenFileName, EnableMenuItem, IsClipboardFormatAvailable, CreateFile, GENERIC_READ, GENERIC_WRITE)

#include <windows.h>

LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);
HINSTANCE g_hInst;
HWND g_hWndMain;
LPSTR lpszClass="SHEditor";
#include "resource.h"

// 함수 원형
void SHLoadFile(void);
void SHSaveFile(BOOL SaveAs);
int ConfirmSave(void);

int APIENTRY WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance
         ,LPSTR lpszCmdParam,int nCmdShow)
{
    HWND hWnd;
    MSG Message;
    WNDCLASS WndClass;
    g_hInst=hInstance;
    
    if(!hPrevInstance) {
        WndClass.cbClsExtra=0;
        WndClass.cbWndExtra=0;
        WndClass.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH);
        WndClass.hCursor=LoadCursor(NULL,IDC_ARROW);
        WndClass.hIcon=LoadIcon(NULL,IDI_APPLICATION);
        WndClass.hInstance=hInstance;
        WndClass.lpfnWndProc=(WNDPROC)WndProc;
        WndClass.lpszClassName=lpszClass;
        WndClass.lpszMenuName=MAKEINTRESOURCE(IDR_MENU1);
        WndClass.style=CS_HREDRAW | CS_VREDRAW;
        RegisterClass(&WndClass);
    }
    hWnd=CreateWindow(lpszClass,"SHEditor-제목없음.txt",WS_OVERLAPPEDWINDOW,
         CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,
         NULL,(HMENU)NULL,hInstance,NULL);
    g_hWndMain=hWnd;
    ShowWindow(hWnd,nCmdShow);

    HACCEL hAccel;

    hAccel=LoadAccelerators(hInstance,MAKEINTRESOURCE(IDR_ACCELERATOR1));
    while(GetMessage(&Message,0,0,0)) {
        if (!TranslateAccelerator(hWnd,hAccel,&Message)) {
            TranslateMessage(&Message);
            DispatchMessage(&Message);
        }
    }
    return Message.wParam;
}

#define IDC_EDIT 100
#define MAXBUFFER 1048576
HWND hEdit;
char NowFile[MAX_PATH]="제목없음.txt";
LRESULT CALLBACK WndProc(HWND hWnd,UINT iMessage,WPARAM wParam,LPARAM lParam)
{
    DWORD Start,End;
    int Result;
    switch(iMessage) {
    case WM_CREATE:
        hEdit=CreateWindow("edit",NULL,WS_CHILD | WS_VISIBLE | ES_AUTOHSCROLL
            | ES_MULTILINE | ES_AUTOVSCROLL | WS_HSCROLL | WS_VSCROLL,
            10,10,200,25,hWnd,(HMENU)IDC_EDIT,g_hInst,NULL);
        SendMessage(hEdit, EM_LIMITTEXT, (WPARAM)MAXBUFFER,0);
        return 0;
    case WM_COMMAND:
        switch (LOWORD(wParam)) {
        case IDM_EDIT_UNDO:
            SendMessage(hEdit, EM_UNDO,0,0);
            return 0;
        case IDM_EDIT_CUT:
            SendMessage(hEdit, WM_CUT,0,0);
            break;
        case IDM_EDIT_COPY:
            SendMessage(hEdit, WM_COPY,0,0);
            break;
        case IDM_EDIT_PASTE:
            SendMessage(hEdit, WM_PASTE,0,0);
            break;
        case IDM_EDIT_DEL:
            SendMessage(hEdit, WM_CLEAR,0,0);
            break;
        case IDM_EDIT_SELALL:
            SendMessage(hEdit, EM_SETSEL,0,-1);
            break;
        case IDM_FILE_NEW:
            Result=ConfirmSave();
            if (Result==IDCANCEL)
                break;
            else if (Result==IDYES)
                SHSaveFile(FALSE);
            SetWindowText(hEdit,"");
            SetWindowText(hWnd,"SHEditor-제목없음.txt");
            strcpy(NowFile,"제목없음.txt");
            break;
        case IDM_FILE_LOAD:
            Result=ConfirmSave();
            if (Result==IDCANCEL)
                break;
            else if (Result==IDYES)
                SHSaveFile(FALSE);
            SHLoadFile();
            break;
        case IDM_FILE_SAVE:
            SHSaveFile(FALSE);
            break;
        case IDM_FILE_SAVEAS:
            SHSaveFile(TRUE);
            break;
        case IDM_FILE_EXIT:
            Result=ConfirmSave();
            if (Result==IDCANCEL)
                break;
            else if (Result==IDYES)
                SHSaveFile(FALSE);
            PostQuitMessage(0);
            break;
        case IDM_HELP_ABOUT:
            MessageBox(hWnd,"간단한 메모장입니다","소개",MB_OK);
            break;
        case IDC_EDIT:
            switch (HIWORD(wParam)) {
            case EN_MAXTEXT:
                MessageBox(hWnd, "입력 문자수 초과","에러",MB_OK);
                break;
            }
        }
        return 0;
    case WM_INITMENU:
        // 취소가 가능한가에 따라 Undo 메뉴 항목을 사용금지/허가한다.
        if (SendMessage(hEdit, EM_CANUNDO,0,0)==TRUE)
            EnableMenuItem(GetMenu(hWnd),ID_ED_UNDO,MF_ENABLED | MF_BYCOMMAND);
        else
            EnableMenuItem(GetMenu(hWnd),ID_ED_UNDO,MF_GRAYED | MF_BYCOMMAND);

        // 선택 영역이 없으면 Cut, Copy, Clear 메뉴 항목은 사용할 수 없다.
        SendMessage(hEdit,EM_GETSEL, (WPARAM)&Start, (LPARAM)&End);
        if (Start != End) {
            EnableMenuItem(GetMenu(hWnd),ID_ED_CUT,MF_ENABLED | MF_BYCOMMAND);
            EnableMenuItem(GetMenu(hWnd),ID_ED_COPY,MF_ENABLED | MF_BYCOMMAND);
            EnableMenuItem(GetMenu(hWnd),ID_ED_DEL,MF_ENABLED | MF_BYCOMMAND);
        }
        else {
            EnableMenuItem(GetMenu(hWnd),ID_ED_CUT,MF_GRAYED | MF_BYCOMMAND);
            EnableMenuItem(GetMenu(hWnd),ID_ED_COPY,MF_GRAYED | MF_BYCOMMAND);
            EnableMenuItem(GetMenu(hWnd),ID_ED_DEL,MF_GRAYED | MF_BYCOMMAND);
        }

        // 클립보드에 텍스트 자료가 없으면 Paste 항목은 사용할 수 없다.
        if (IsClipboardFormatAvailable(CF_TEXT))
            EnableMenuItem(GetMenu(hWnd),ID_ED_PASTE,MF_ENABLED | MF_BYCOMMAND);
        else
            EnableMenuItem(GetMenu(hWnd),ID_ED_PASTE,MF_GRAYED | MF_BYCOMMAND);
        return 0;
    case WM_CLOSE:
        Result=ConfirmSave();
        if (Result==IDCANCEL)
            break;
        else if (Result==IDYES)
            SHSaveFile(FALSE);
        break;
    case WM_SIZE:
        MoveWindow(hEdit, 0, 0, LOWORD(lParam), HIWORD(lParam),TRUE);
        return 0;
    case WM_SETFOCUS:
        SetFocus(hEdit);
        return 0;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    }
    return(DefWindowProc(hWnd,iMessage,wParam,lParam));
}

// 파일을 읽어온다.
void SHLoadFile(void)
{
    OPENFILENAME OFN;
    char lpstrFile[MAX_PATH]="";
    HANDLE hFile;
    char *pBuf;
    DWORD dwSize;

    memset(&OFN, 0, sizeof(OPENFILENAME));
    OFN.lStructSize = sizeof(OPENFILENAME);
    OFN.hwndOwner=g_hWndMain;
    OFN.lpstrFilter="Text File\0*.txt;*.doc\0Every File(*.*)\0*.*\0";
    OFN.lpstrFile=lpstrFile;
    OFN.nMaxFile=256;
    OFN.lpstrInitialDir="c:\\";

    if (GetOpenFileName(&OFN)!=0) {
        pBuf=(char *)malloc(MAXBUFFER);
        strcpy(NowFile,OFN.lpstrFile);
        hFile=CreateFile(OFN.lpstrFile,GENERIC_READ,0,NULL,
            OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL,NULL);
        ReadFile((HANDLE)hFile, pBuf, MAXBUFFER, &dwSize, NULL);
        pBuf[dwSize]=0;
        SetWindowText(hEdit,(LPCTSTR)pBuf);
        CloseHandle(hFile);
        wsprintf(pBuf,"SHEditor-%s",NowFile);
        SetWindowText(g_hWndMain,(LPCTSTR)pBuf);
        free(pBuf);

        SendMessage(hEdit,EM_SETMODIFY,(WPARAM)FALSE,0);
    }
}

// 현재 편집중인 파일을 저장한다.
void SHSaveFile(BOOL SaveAs)
{
    OPENFILENAME OFN;
    char lpstrFile[MAX_PATH]="";
    HANDLE hFile;
    char *pBuf;
    int length;
    DWORD Written;
    BOOL bResult=TRUE;;
    char FilePath[MAX_PATH];

    memset(&OFN, 0, sizeof(OPENFILENAME));
    OFN.lStructSize = sizeof(OPENFILENAME);
    OFN.hwndOwner=g_hWndMain;
    OFN.lpstrFilter="Text File\0*.txt;*.doc\0Every File(*.*)\0*.*\0";
    OFN.lpstrFile=lpstrFile;
    OFN.nMaxFile=256;
    OFN.lpstrInitialDir="c:\\";

    if (strcmp(NowFile,"제목없음.txt")==0 || SaveAs==TRUE) {
        bResult=GetSaveFileName(&OFN);
        strcpy(FilePath,OFN.lpstrFile);
    }
    else {
        strcpy(FilePath,NowFile);
    }

    if (bResult!=FALSE) {
        pBuf=(char *)malloc(MAXBUFFER);
        length=GetWindowText(hEdit,pBuf,MAXBUFFER);
        hFile=CreateFile(FilePath,GENERIC_WRITE,0,NULL,
            CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL,NULL);
        WriteFile(hFile,pBuf,length,&Written,NULL);
        CloseHandle(hFile);
        wsprintf(pBuf,"SHEditor-%s",FilePath);
        SetWindowText(g_hWndMain,(LPCTSTR)pBuf);
        strcpy(NowFile,FilePath);
        free(pBuf);

        SendMessage(hEdit,EM_SETMODIFY,(WPARAM)FALSE,0);
    }
}

// 미보관 파일의 저장 여부를 질문한다.
int ConfirmSave(void)
{
    if (SendMessage(hEdit,EM_GETMODIFY,0,0)==TRUE) {
        return MessageBox(g_hWndMain,"편집하던 파일을 저장하시겠습니까?",
            "확인",MB_YESNOCANCEL);
    }
    else
        return IDNO;
}