[핵심 API로 배우는 윈도우프로그래밍(강경우, 한빛아카데미)] 8장 2번 풀이

#include <Windows.h>
#include<tchar.h>
#include<string.h>
#include"resource.h"
#include<winres.h>
//#pragma comment(linker,"/entry:WinMainCRTStartup /subsystem:console")
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam);
HINSTANCE hInst;
void FileWrite(HWND hwnd, LPTSTR filename)
{
    HANDLE hFile;
    LPTSTR buffer;
    int size;
 
    hFile = CreateFile(filename, GENERIC_WRITE, 0, 0, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);
    size = GetWindowTextLength(hwnd);
    buffer = new TCHAR[size + 1];
    memset(buffer, 0, (size + 1) * sizeof(TCHAR));
    GetWindowText(hwnd, buffer, size + 1);
    buffer[size] = NULL;
    WriteFile(hFile, buffer, (size) * sizeof(TCHAR), (LPDWORD)&size, NULL);
    free(buffer);
    CloseHandle(hFile);
 
}
void FileRead(HWND hwnd, LPTSTR filename)
{
    HANDLE hFile;
    LPTSTR buffer; 
    DWORD size, CharNum;
    int fileSize;
 
    hFile = CreateFile(filename, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, 0);
    if (hFile == INVALID_HANDLE_VALUE) return;
    fileSize =GetFileSize(hFile, &size);
    buffer = new TCHAR[(int)fileSize / sizeof(TCHAR) + 1];
    memset(buffer, 0, fileSize);
    ReadFile(hFile, buffer, fileSize, &CharNum, NULL);
    buffer[(int)fileSize / sizeof(TCHAR)] = NULL;
    SetWindowText(hwnd, buffer);
    free(buffer);
    CloseHandle(hFile);
}
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpszCmdLine, int nCmdShow)
{
    HWND hwnd;
    MSG msg;
    WNDCLASS WndClass;
 
    hInst = hInstance;
    WndClass.style = CS_HREDRAW | CS_VREDRAW;
    WndClass.lpfnWndProc = WndProc;
    WndClass.cbClsExtra = 0;
    WndClass.cbWndExtra = 0;
    WndClass.hInstance = hInstance;
    WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    WndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
    WndClass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    WndClass.lpszMenuName = MAKEINTRESOURCE(IDR_MENU1);
    WndClass.lpszClassName = _T("Window Class Name");
 
    RegisterClass(&WndClass);
 
    hwnd = CreateWindow(
        _T("Window Class Name"),
        _T("박정호"),
        WS_OVERLAPPEDWINDOW,
        50,
        50,
        1000,
        700,
        NULL,
        NULL,
        hInstance,
        NULL);
 
    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);
 
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return (int)msg.wParam;
}
#define IDC_EDIT1 100
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
    HDC hdc;
    RECT rect;
    PAINTSTRUCT ps;
    OPENFILENAME OFN,SFN;
    static TCHAR filepath[1000], filename[100];
    TCHAR filter[] = _T("텍스트 파일 (*.txt)\0*.txt\0모든 파일 (*.*)\0*.*\0");
    static HWND hEdit;
 
    switch (iMsg)
    {
    case WM_CREATE:
        GetClientRect(hwnd, &rect);
        hEdit = CreateWindow(
            _T("edit"), NULL, WS_CHILD | WS_VISIBLE | WS_HSCROLL | WS_VSCROLL |    
            ES_AUTOHSCROLL | ES_AUTOVSCROLL | ES_MULTILINE, 0, 100,
            rect.right, rect.bottom, hwnd, (HMENU)IDC_EDIT1, hInst, NULL);
        break;
    case WM_SIZE:
        GetClientRect(hwnd, &rect);
        MoveWindow(hEdit, 0, 0, rect.right, rect.bottom, TRUE);
        break;
    case WM_COMMAND:
        switch (LOWORD(wParam))
        {
        case ID_FILEOPEN:
            memset(&OFN, 0, sizeof(OPENFILENAME));
            OFN.lStructSize = sizeof(OPENFILENAME);
            OFN.hwndOwner = hwnd;
            OFN.lpstrFile = filepath;
            OFN.nMaxFile = 1000;
            OFN.lpstrFileTitle = filename;
            OFN.nMaxFileTitle = 100;
            OFN.lpstrFilter = filter;
            OFN.Flags = OFN_EXPLORER;
            OFN.lpstrInitialDir = _T(".");
            GetOpenFileName(&OFN);
 
            FileRead(hEdit, filepath);
            break;
        case ID_FILESAVE:
            memset(&SFN, 0, sizeof(OPENFILENAME));
            SFN.lStructSize = sizeof(OPENFILENAME);
            SFN.hwndOwner = hwnd;
            SFN.lpstrFilter = filter;
            SFN.lpstrFile = filepath;
            SFN.nMaxFile = 1000;
            SFN.lpstrInitialDir = _T(".");
            GetSaveFileName(&SFN);
 
            FileWrite(hEdit, filepath);
            break;
        }
        break;
    case WM_PAINT:
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
 
    }
    return DefWindowProc(hwnd, iMsg, wParam, lParam);
}