C语言 vs2022 Win32API COM 读取 Excel 表格的工具类

以下是一个简单的工具类，可以在 C++ 中使用 Win32API 和 COM 技术读取 Excel 表格：

#include <Windows.h>
#include <ole2.h>
#include <stdio.h>
#include <tchar.h>

class ExcelReader {
public:
    ExcelReader() : m_pExcelApp(NULL), m_pWorkbooks(NULL), m_pWorkbook(NULL), m_pSheet(NULL) {}
    ~ExcelReader() { Close(); }

    bool Open(const TCHAR* szFile, const TCHAR* szSheet = NULL) {
        if (szFile == NULL || szFile[0] == _T('\0')) {
            return false;
        }

        // 初始化 COM 库
        CoInitialize(NULL);

        // 打开 Excel 应用程序
        m_pExcelApp = NULL;
        if (FAILED(CoCreateInstance(CLSIDExcelApplication, NULL, CLSCTX_LOCAL_SERVER, IID_IDispatch, (void**)&m_pExcelApp))) {
            return false;
        }

        // 显示 Excel 应用程序
        m_pExcelApp->PutVisible(VARIANT_TRUE);

        // 获取 Workbooks 对象
        m_pWorkbooks = m_pExcelApp->GetWorkbooks();
        if (m_pWorkbooks == NULL) {
            return false;
        }

        // 打开工作簿
        m_pWorkbook = m_pWorkbooks->Open(szFile);
        if (m_pWorkbook == NULL) {
            return false;
        }

        // 获取 Sheets 对象
        m_pSheets = m_pWorkbook->GetSheets();
        if (m_pSheets == NULL) {
            return false;
        }

        // 选择指定的工作表
        if (szSheet != NULL && szSheet[0] != _T('\0')) {
            m_pSheet = m_pSheets->GetItem(COleVariant(szSheet));
            if (m_pSheet == NULL) {
                return false;
            }
        }
        else {
            m_pSheet = m_pSheets->GetItem(COleVariant((short)1));
        }

        return true;
    }

    void Close() {
        if (m_pSheet != NULL) {
            m_pSheet->Release();
            m_pSheet = NULL;
        }

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

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

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

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

        // 反初始化 COM 库
        CoUninitialize();
    }

    int GetRowCount() const {
        if (m_pSheet == NULL) {
            return 0;
        }

        COleVariant vResult;
        COleVariant vProp((short)7); // XlRangeValueDataType.xlRangeValueDefault

        // 获取行数
        LPDISPATCH pDisp = m_pSheet->GetUsedRange();
        if (pDisp == NULL) {
            return 0;
        }

        IDispatch* pRow = NULL;
        IDispatch* pColumns = NULL;
        int nRowCount = 0;
        int nColumnCount = 0;
        try {
            pRow = pDisp->GetIDispatch(TRUE);
            pColumns = pDisp->GetIDispatch(FALSE);

            COleVariant vRowCount;
            vRowCount.vt = VT_I4;
            vRowCount.lVal = 1;

            COleVariant vColumnCount;
            vColumnCount.vt = VT_I4;
            vColumnCount.lVal = 1;

            DISPID dispid;
            LPOLESTR lpszMember = _T("Rows");
            if (FAILED(pColumns->GetIDsOfNames(IID_NULL, &lpszMember, 1, LOCALE_USER_DEFAULT, &dispid))) {
                throw;
            }
            if (FAILED(pColumns->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, NULL, &vResult, NULL, NULL))) {
                throw;
            }
            IDispatch* pRows = vResult.pdispVal;

            DISPPARAMS dispparams = { NULL, NULL, 0, 0 };
            if (FAILED(pRows->Invoke(DISPID_ITEM, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparams, &vResult, NULL, NULL))) {
                throw;
            }
            nRowCount = vResult.lVal;

            lpszMember = _T("Columns");
            if (FAILED(pRow->GetIDsOfNames(IID_NULL, &lpszMember, 1, LOCALE_USER_DEFAULT, &dispid))) {
                throw;
            }
            if (FAILED(pRow->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, NULL, &vResult, NULL, NULL))) {
                throw;
            }
            IDispatch* pColumns = vResult.pdispVal;

            if (FAILED(pColumns->Invoke(DISPID_ITEM, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparams, &vResult, NULL, NULL))) {
                throw;
            }
            nColumnCount = vResult.lVal;
        }
        catch (...) {
            if (pRow != NULL) {
                pRow->Release();
            }
            if (pColumns != NULL) {
                pColumns->Release();
            }
            if (pDisp != NULL) {
                pDisp->Release();
            }
            return 0;
        }

        if (pRow != NULL) {
            pRow->Release();
        }
        if (pColumns != NULL) {
            pColumns->Release();
        }
        if (pDisp != NULL) {
            pDisp->Release();
        }

        return nRowCount;
    }

    int GetColumnCount() const {
        if (m_pSheet == NULL) {
            return 0;
        }

        COleVariant vResult;
        COleVariant vProp((short)7); // XlRangeValueDataType.xlRangeValueDefault

        // 获取列数
        LPDISPATCH pDisp = m_pSheet->GetUsedRange();
        if (pDisp == NULL) {
            return 0;
        }

        IDispatch* pRow = NULL;
        IDispatch* pColumns = NULL;
        int nRowCount = 0;
        int nColumnCount = 0;
        try {
            pRow = pDisp->GetIDispatch(TRUE);
            pColumns = pDisp->GetIDispatch(FALSE);

            COleVariant vRowCount;
            vRowCount.vt = VT_I4;
            vRowCount.lVal = 1;

            COleVariant vColumnCount;
            vColumnCount.vt = VT_I4;
            vColumnCount.lVal = 1;

            DISPID dispid;
            LPOLESTR lpszMember = _T("Rows");
            if (FAILED(pColumns->GetIDsOfNames(IID_NULL, &lpszMember, 1, LOCALE_USER_DEFAULT, &dispid))) {
                throw;
            }
            if (FAILED(pColumns->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, NULL, &vResult, NULL, NULL))) {
                throw;
            }
            IDispatch* pRows = vResult.pdispVal;

            DISPPARAMS dispparams = { NULL, NULL, 0, 0 };
            if (FAILED(pRows->Invoke(DISPID_ITEM, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparams, &vResult, NULL, NULL))) {
                throw;
            }
            nRowCount = vResult.lVal;

            lpszMember = _T("Columns");
            if (FAILED(pRow->GetIDsOfNames(IID_NULL, &lpszMember, 1, LOCALE_USER_DEFAULT, &dispid))) {
                throw;
            }
            if (FAILED(pRow->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, NULL, &vResult, NULL, NULL))) {
                throw;
            }
            IDispatch* pColumns = vResult.pdispVal;

            if (FAILED(pColumns->Invoke(DISPID_ITEM, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparams, &vResult, NULL, NULL))) {
                throw;
            }
            nColumnCount = vResult.lVal;
        }
        catch (...) {
            if (pRow != NULL) {
                pRow->Release();
            }
            if (pColumns != NULL) {
                pColumns->Release();
            }
            if (pDisp != NULL) {
                pDisp->Release();
            }
            return 0;
        }

        if (pRow != NULL) {
            pRow->Release();
        }
        if (pColumns != NULL) {
            pColumns->Release();
        }
        if (pDisp != NULL) {
            pDisp->Release();
        }

        return nColumnCount;
    }

    bool ReadCell(int nRow, int nCol, CString& strValue) const {
        if (m_pSheet == NULL) {
            return false;
        }

        COleVariant vResult;
        COleVariant vProp((short)7); // XlRangeValueDataType.xlRangeValueDefault

        // 读取单元格的值
        COleVariant vRow((short)nRow);
        COleVariant vCol((short)nCol);
        LPDISPATCH pDisp = m_pSheet->GetCells();
        if (pDisp == NULL) {
            return false;
        }

        IDispatch* pCell = NULL;
        try {
            if (FAILED(pDisp->Invoke(DISPID_ITEM, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &vRow, &vResult, NULL, NULL))) {
                throw;
            }
            pCell = vResult.pdispVal;

            DISPID dispid;
            LPOLESTR lpszMember = _T("Item");
            if (FAILED(pCell->GetIDsOfNames(IID_NULL, &lpszMember, 1, LOCALE_USER_DEFAULT, &dispid))) {
                throw;
            }
            DISPPARAMS dispparams = { NULL, NULL, 0, 0 };
            if (FAILED(pCell->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparams, &vResult, NULL, NULL))) {
                throw;
            }

            if (vResult.vt == VT_BSTR) {
                strValue = CString(vResult.bstrVal);
            }
            else {
                strValue.Empty();
            }
        }
        catch (...) {
            if (pCell != NULL) {
                pCell->Release();
            }
            if (pDisp != NULL) {
                pDisp->Release();
            }
            return false;
        }

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

        return true;
    }

private:
    IDispatch* m_pExcelApp;     // Excel 应用程序对象
    IDispatch* m_pWorkbooks;    // Workbooks 对象
    IDispatch* m_pWorkbook;     // Workbook 对象
    IDispatch* m_pSheets;       // Sheets 对象
    IDispatch* m_pSheet;        // Worksheet 对象
};

使用示例：

ExcelReader reader;
if (!reader.Open(_T("C:\\test.xls"), _T("Sheet1"))) {
    printf("Open file failed!\n");
    return;
}

int nRowCount = reader.GetRowCount();
int nColumnCount = reader.GetColumnCount();
for (int i = 1; i <= nRowCount; i++) {
    for (int j = 1; j <= nColumnCount; j++) {
        CString strValue;
        if (reader.ReadCell(i, j, strValue)) {
            printf("%s\t", strValue);
        }
    }
    printf("\n");
}

reader.Close();

需要注意的是，该工具类依赖于 Microsoft Office Excel 应用程序，因此需要在使用前确保已经安装了 Excel 并且系统中有相应的 COM 组件。同时，该工具类只能在 Windows 平台下使用，无法在 Linux、macOS 等其他操作系统上编译和运行。