Win32API COM读取Excel表格源码 封装工具类

以下是一个简单的 Win32API COM 读取 Excel 表格的工具类封装源码：

#include <Windows.h>
#include <Ole2.h>
#include <OleAuto.h>
#include <iostream>
#include <string>

using namespace std;

class ExcelReader
{
public:
    ExcelReader();
    ~ExcelReader();

    bool Open(const char* filename);
    void Close();
    bool ReadCell(int row, int col, string& str);

private:
    bool Init();
    bool Uninit();

private:
    HRESULT m_hr;
    IDispatch* m_pExcelApp;
    _Application* m_pExcel;
    Workbooks* m_pBooks;
    _Workbook* m_pBook;
    Worksheets* m_pSheets;
    _Worksheet* m_pSheet;
};

ExcelReader::ExcelReader()
    :m_hr(S_OK), m_pExcelApp(NULL), m_pExcel(NULL), m_pBooks(NULL), m_pBook(NULL), m_pSheets(NULL), m_pSheet(NULL)
{
    Init();
}

ExcelReader::~ExcelReader()
{
    Uninit();
}

bool ExcelReader::Init()
{
    m_hr = CoInitialize(NULL);
    if (FAILED(m_hr))
    {
        return false;
    }

    m_hr = CoCreateInstance(CLSID_Application, NULL, CLSCTX_LOCAL_SERVER, IID_IDispatch, (void**)&m_pExcelApp);
    if (FAILED(m_hr))
    {
        return false;
    }

    m_pExcel = (_Application*)m_pExcelApp;
    m_pBooks = m_pExcel->Workbooks;
    return true;
}

bool ExcelReader::Uninit()
{
    if (m_pSheet != NULL)
    {
        m_pSheet->Release();
        m_pSheet = NULL;
    }

    if (m_pSheets != NULL)
    {
        m_pSheets->Release();
        m_pSheets = NULL;
    }

    if (m_pBook != NULL)
    {
        m_pBook->Close(VARIANT_TRUE);
        m_pBook->Release();
        m_pBook = NULL;
    }

    if (m_pBooks != NULL)
    {
        m_pBooks->Release();
        m_pBooks = NULL;
    }

    if (m_pExcel != NULL)
    {
        m_pExcel->Quit();
        m_pExcel = NULL;
    }

    if (m_pExcelApp != NULL)
    {
        m_pExcelApp->Release();
        m_pExcelApp = NULL;
    }

    CoUninitialize();
    return true;
}

bool ExcelReader::Open(const char* filename)
{
    if (m_pExcel == NULL)
    {
        return false;
    }

    m_pBook = m_pBooks->Open(_bstr_t(filename));

    if (m_pBook == NULL)
    {
        return false;
    }

    m_pSheets = m_pBook->Worksheets;
    m_pSheet = (_Worksheet*)m_pSheets->Item(1);

    if (m_pSheet == NULL)
    {
        return false;
    }

    return true;
}

void ExcelReader::Close()
{
    Uninit();
}

bool ExcelReader::ReadCell(int row, int col, string& str)
{
    if (m_pSheet == NULL)
    {
        return false;
    }

    _variant_t val;
    val = m_pSheet->Cells->Item[row][col]->Value;
    if (val.vt == VT_NULL)
    {
        return false;
    }

    _bstr_t bstr = val;
    str = (char*)bstr;
    return true;
}

使用方法：

ExcelReader reader;
if (!reader.Open("test.xlsx"))
{
    cout << "Open file failed." << endl;
    return 0;
}

string cell_value;
if (reader.ReadCell(1, 1, cell_value))
{
    cout << "Cell value: " << cell_value << endl;
}
else
{
    cout << "Read cell failed." << endl;
}

reader.Close();

注意，需要在代码中引入 `Ole2.h`、`OleAuto.h` 头文件，并且在工程链接时需要添加 `Ole32.lib`、`OleAut32.lib` 库文件。