如何修复<程序名称>中的"<内存位置>未处理的异常。Visual Studio 2017 中的访问冲突写入位置<内存位置>"

我正在使用库libxl编写代码以在excel中制作发票。我的代码创建一个文件，写入该文件，然后将该文件保存在项目文件夹中。

但是，当我进行调试时，我看到一个"未处理的异常"，在写入特定位置时存在访问冲突。该异常实际上显示"BillingSoft.exe：0xC0000005：访问违规写入位置0x00C3DED4.0x100437D7（libxl.dll）的未处理异常"。我已经阅读了许多文章和解决方案，但似乎都没有解决我的问题。我尝试使用

    Book* book = (Book*)malloc(sizeof(book));

在声明"book"之前，但它只是更改位置值，并不能解决问题。

这是我的主要功能：

    int main()
    { 
    Book* book = xlCreateBook(); // xlCreateXMLBook() for xlsx
if (book)
{
    Font* boldFont = book->addFont();
    boldFont->setBold();
    Font* titleFont = book->addFont();
    titleFont->setName(L"Arial Black");
    titleFont->setSize(16);
    Format* titleFormat = book->addFormat();
    if (titleFormat = nullptr)
    {
        titleFormat->setFont(titleFont);
    }
    Format* headerFormat = book->addFormat();
    if (headerFormat = nullptr)
    {
        headerFormat->setAlignH(ALIGNH_CENTER);
        headerFormat->setBorder(BORDERSTYLE_THIN);
        headerFormat->setFont(boldFont);
        headerFormat->setFillPattern(FILLPATTERN_SOLID);
        headerFormat->setPatternForegroundColor(COLOR_TAN);
    }
    Format* descriptionFormat = book->addFormat();
    if (descriptionFormat = nullptr)
    {
        descriptionFormat->setBorderLeft(BORDERSTYLE_THIN);
    }
    Format* amountFormat = book->addFormat();
    if (amountFormat = nullptr)
    {
        amountFormat->setNumFormat(NUMFORMAT_CURRENCY_NEGBRA);
        amountFormat->setBorderLeft(BORDERSTYLE_THIN);
        amountFormat->setBorderRight(BORDERSTYLE_THIN);
    }
    Format* totalLabelFormat = book->addFormat();
    if (totalLabelFormat = nullptr)
    {
        totalLabelFormat->setBorderTop(BORDERSTYLE_THIN);
        totalLabelFormat->setAlignH(ALIGNH_RIGHT);
        totalLabelFormat->setFont(boldFont);
    }
    Format* totalFormat = book->addFormat();
    if (totalFormat = nullptr)
    {
        totalFormat->setNumFormat(NUMFORMAT_CURRENCY_NEGBRA);
        totalFormat->setBorder(BORDERSTYLE_THIN);
        totalFormat->setFont(boldFont);
        totalFormat->setFillPattern(FILLPATTERN_SOLID);
        totalFormat->setPatternForegroundColor(COLOR_YELLOW);
    }
    Format* signatureFormat = book->addFormat();
    if (signatureFormat = nullptr)
    {
        signatureFormat->setAlignH(ALIGNH_CENTER);
        signatureFormat->setBorderTop(BORDERSTYLE_THIN);
    }
    Sheet* sheet = book->addSheet(L"Sheet1");
    if (sheet)
    {
        sheet->writeStr(2, 1, L"Invoice No. 3568", titleFormat);
        sheet->writeStr(4, 1, L"Name: John Smith");
        sheet->writeStr(5, 1, L"Address: San Ramon, CA 94583 USA");
        sheet->writeStr(7, 1, L"Description", headerFormat);
        sheet->writeStr(7, 2, L"Amount", headerFormat);
        sheet->writeStr(8, 1, L"Ball-Point Pens", descriptionFormat);
        sheet->writeNum(8, 2, 85, amountFormat);
        sheet->writeStr(9, 1, L"T-Shirts", descriptionFormat);
        sheet->writeNum(9, 2, 150, amountFormat);
        sheet->writeStr(10, 1, L"Tea cups", descriptionFormat);
        sheet->writeNum(10, 2, 45, amountFormat);
        sheet->writeStr(11, 1, L"Total:", totalLabelFormat);
        sheet->writeNum(11, 2, 280, totalFormat);
        sheet->writeStr(14, 2, L"Signature", signatureFormat);
        sheet->setCol(1, 1, 40);
        sheet->setCol(2, 2, 15);
    }
    book->save(L"Invoice.xls"); // exception here!
    book->release();
}
return 0;
    }

我只是希望程序正常工作而没有任何错误。请帮我解决我的问题。任何帮助将不胜感激！