錯誤：操作成功完成（使用WindowsAPI的C 命令列游戲引擎）

如標題所述，我想使用命令列控制臺撰寫游戲引擎。緊跟oneLoneCoder的專案，目前我寫的代碼如下。在檢查用戶提供的尺寸是否正確后，它會創建一個命令控制臺。

#include <Windows.h>
#include <iostream>
#include <cassert>

namespace CmdLineConsoleEngine {

    void Error(const HANDLE& hConsole, const wchar_t* msg) {
    
        wchar_t buf[256];
        FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, 256, NULL);
        SetConsoleActiveScreenBuffer(hConsole);
        wprintf(L"ERROR: %s\n\t%s\n", msg, buf);
        exit(-1);
    }

    auto CreateConsole() -> HANDLE {

        HANDLE hConsole = CreateConsoleScreenBuffer(GENERIC_READ | GENERIC_WRITE, 0, NULL, CONSOLE_TEXTMODE_BUFFER, NULL);
        if (hConsole == INVALID_HANDLE_VALUE)
            Error(hConsole, L"Bad Handle"); // in which cases does this occur?
        else {
            SetConsoleActiveScreenBuffer(hConsole);
        }
        return hConsole;
    }

    void CheckConsoleSize(const HANDLE& hConsole, int screenWidth, int screenHeight) {

        assert(hConsole != nullptr);
        assert(screenWidth > 0);
        assert(screenHeight > 0);

        const COORD largestSize = GetLargestConsoleWindowSize(hConsole);
        if (screenWidth > largestSize.X) 
            Error(hConsole, L"The width dimension is too large.");
        if (screenHeight > largestSize.Y) 
            Error(hConsole, L"The height dimension is too large.");
        return;
    }

    void SetConsoleWindowSize(HANDLE& hConsole, int screenWidth, int screenHeight) {

        CheckConsoleSize(hConsole, screenWidth, screenHeight);

        const SMALL_RECT minimalRectWindow = { 0, 0, 12, 6 };
        SetConsoleWindowInfo(hConsole, TRUE, &minimalRectWindow);

        COORD coord = {static_cast<short>(screenWidth), static_cast<short>(screenHeight)};
        if (!SetConsoleScreenBufferSize(hConsole, coord))
            Error(hConsole, L"SetConsoleScreenBufferSize");

        SMALL_RECT rectWindow = {0, 0, static_cast<short>(screenWidth - 1), static_cast<short>(screenHeight - 1)};
        if (!SetConsoleWindowInfo(hConsole, TRUE, &rectWindow))
            Error(hConsole, L"SetConsoleWindowInfo");
        return;
    }

    void WriteToConsole(const HANDLE& hConsole, const wchar_t* screen, int screenWidth, int screenHeight) {

        DWORD dwBytesWritten = 0;
        WriteConsoleOutputCharacter(hConsole, screen, screenWidth * screenHeight, { 0,0 }, &dwBytesWritten);
    }

}

int main() {

    HANDLE hConsole = CmdLineConsoleEngine::CreateConsole();
    int screenWidth = 160;
    int screenHeight = 140;
    CmdLineConsoleEngine::SetConsoleWindowSize(hConsole, screenWidth, screenHeight);
    return 0;
}

執行main()函式，我得到的輸出是

ERROR: The height dimension is too large.
The operation completed successfully.    

它是一個Error有趣的功能。為方便起見，呼叫層次結構是SetConsoleWindowSize -> CheckConsoleSize -> Error

關于為什么會發生這種情況的任何想法？

uj5u.com熱心網友回復：

你的錯誤報告CheckConsoleSize()是錯誤的。GetLastError()僅當GetLargestConsoleWindowSize()回傳COORD包含所有零的a時才有意義，您沒有檢查它。您所描述的內容聽起來像是COORD只包含比您預期的要小的尺寸，但不是零。這就是為什么GetLastError()回傳 0，因此FormatMessage()回傳"The operation completed successfully"。

嘗試更像這樣的事情：

#include <Windows.h>
#include <iostream>
#include <cassert>

namespace CmdLineConsoleEngine {

    void Error(HANDLE hConsole, const wchar_t* msg) {
        SetConsoleActiveScreenBuffer(hConsole);
        wprintf(L"ERROR: %s\n", msg);
        exit(-1);
    }

    void ErrorWithCode(HANDLE hConsole, const wchar_t* msg, DWORD ErrorCode = GetLastError()) {
        wchar_t buf[256] = {};
        FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM, NULL, ErrorCode, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, 256, NULL);
        SetConsoleActiveScreenBuffer(hConsole);
        wprintf(L"ERROR: %s\n\t%s\n", msg, buf);
        exit(-1);
    }

    HANDLE CreateConsole() {
        HANDLE hConsole = CreateConsoleScreenBuffer(GENERIC_READ | GENERIC_WRITE, 0, NULL, CONSOLE_TEXTMODE_BUFFER, NULL);
        if (hConsole == INVALID_HANDLE_VALUE)
            ErrorWithCode(hConsole, L"Bad Handle"); // in which cases does this occur?
        SetConsoleActiveScreenBuffer(hConsole);
        return hConsole;
    }

    void DestroyConsole(HANDLE& hConsole) {
        if (hConsole != INVALID_HANDLE_VALUE) {
            CloseHandle(hConsole);
            hConsole = INVALID_HANDLE_VALUE;
        }
    }

    void CheckConsoleSize(HANDLE hConsole, int screenWidth, int screenHeight) {
        assert(hConsole != INVALID_HANDLE_VALUE);
        assert(screenWidth > 0);
        assert(screenHeight > 0);
        const COORD largestSize = GetLargestConsoleWindowSize(hConsole);
        if (largestSize.X == 0 && largestSize.Y == 0) 
            ErrorWithCode(hConsole, L"GetLargestConsoleWindowSize");
        if (screenWidth > largestSize.X) 
            Error(hConsole, L"The width dimension is too large.");
        if (screenHeight > largestSize.Y) 
            Error(hConsole, L"The height dimension is too large.");
    }

    void SetConsoleWindowSize(HANDLE hConsole, int screenWidth, int screenHeight) {
        CheckConsoleSize(hConsole, screenWidth, screenHeight);

        const SMALL_RECT minimalRectWindow = { 0, 0, 12, 6 };
        if (!SetConsoleWindowInfo(hConsole, TRUE, &minimalRectWindow))
            ErrorWithCode(hConsole, L"SetConsoleWindowInfo");

        COORD coord = {static_cast<short>(screenWidth), static_cast<short>(screenHeight)};
        if (!SetConsoleScreenBufferSize(hConsole, coord))
            ErrorWithCode(hConsole, L"SetConsoleScreenBufferSize");

        SMALL_RECT rectWindow = {0, 0, static_cast<short>(screenWidth - 1), static_cast<short>(screenHeight - 1)};
        if (!SetConsoleWindowInfo(hConsole, TRUE, &rectWindow))
            ErrorWithCode(hConsole, L"SetConsoleWindowInfo");
    }

    void WriteToConsole(HANDLE hConsole, const wchar_t* screen, int screenWidth, int screenHeight) {
        DWORD dwBytesWritten = 0;
        if (!WriteConsoleOutputCharacter(hConsole, screen, screenWidth * screenHeight, {0, 0}, &dwBytesWritten))
            ErrorWithCode(hConsole, L"WriteConsoleOutputCharacter");
    }
}

int main() {
    HANDLE hConsole = CmdLineConsoleEngine::CreateConsole();
    CmdLineConsoleEngine::SetConsoleWindowSize(hConsole, 160, 140);
    CmdLineConsoleEngine::DestroyConsole(hConsole);
    return 0;
}

附帶說明：Error/WithCode()如果CreateConsoleScreenBuffer()失敗則呼叫沒有意義，因為您將SetConsoleActiveScreenBuffer()使用無效的控制臺句柄進行呼叫。

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