~~~~~~****我已经将EXCEL的单元格内容读到VARAIANT类型的变量中，怎样才能取出其中的字符串啊？

Question

一般来说是这个，myvariant.bstrVal你可以判断一下myvariant.vt == VT_BSTR 还是其他的值from msdn:
-------------------------------typedef struct FARSTRUCT tagVARIANT VARIANT;
typedef struct FARSTRUCT tagVARIANT VARIANTARG;typedef struct tagVARIANT  {
   VARTYPE vt;
   unsigned short wReserved1;
   unsigned short wReserved2;
   unsigned short wReserved3;
   union {
      Byte                    bVal;                 // VT_UI1.
      Short                   iVal;                 // VT_I2.
      long                    lVal;                 // VT_I4.
      float                   fltVal;               // VT_R4.
      double                  dblVal;               // VT_R8.
      VARIANT_BOOL            boolVal;              // VT_BOOL.
      SCODE                   scode;                // VT_ERROR.
      CY                      cyVal;                // VT_CY.
      DATE                    date;                 // VT_DATE.
      BSTR                    bstrVal;              // VT_BSTR.
      DECIMAL                 FAR* pdecVal          // VT_BYREF|VT_DECIMAL.
      IUnknown                FAR* punkVal;         // VT_UNKNOWN.
      IDispatch               FAR* pdispVal;        // VT_DISPATCH.
      SAFEARRAY               FAR* parray;          // VT_ARRAY|*.
      Byte                    FAR* pbVal;           // VT_BYREF|VT_UI1.
      short                   FAR* piVal;           // VT_BYREF|VT_I2.
      long                    FAR* plVal;           // VT_BYREF|VT_I4.
      float                   FAR* pfltVal;         // VT_BYREF|VT_R4.
      double                  FAR* pdblVal;         // VT_BYREF|VT_R8.
      VARIANT_BOOL            FAR* pboolVal;        // VT_BYREF|VT_BOOL.
      SCODE                   FAR* pscode;          // VT_BYREF|VT_ERROR.
      CY                      FAR* pcyVal;          // VT_BYREF|VT_CY.
      DATE                    FAR* pdate;           // VT_BYREF|VT_DATE.
      BSTR                    FAR* pbstrVal;        // VT_BYREF|VT_BSTR.
      IUnknown                FAR* FAR* ppunkVal;   // VT_BYREF|VT_UNKNOWN.
      IDispatch               FAR* FAR* ppdispVal;  // VT_BYREF|VT_DISPATCH.
      SAFEARRAY               FAR* FAR* pparray;    // VT_ARRAY|*.
      VARIANT                 FAR* pvarVal;         // VT_BYREF|VT_VARIANT.
      void                    FAR* byref;           // Generic ByRef.
      char                    cVal;                 // VT_I1.
      unsigned short          uiVal;                // VT_UI2.
      unsigned long           ulVal;                // VT_UI4.
      int                     intVal;               // VT_INT.
      unsigned int            uintVal;              // VT_UINT.
      char FAR *              pcVal;                // VT_BYREF|VT_I1.
      unsigned short FAR *    puiVal;               // VT_BYREF|VT_UI2.
      unsigned long FAR *     pulVal;               // VT_BYREF|VT_UI4.
      int FAR *               pintVal;              // VT_BYREF|VT_INT.
      unsigned int FAR *      puintVal;             //VT_BYREF|VT_UINT.
   };
};

Answer 1

一般来说是这个，myvariant.bstrVal你可以判断一下myvariant.vt == VT_BSTR 还是其他的值from msdn:
-------------------------------typedef struct FARSTRUCT tagVARIANT VARIANT;
typedef struct FARSTRUCT tagVARIANT VARIANTARG;typedef struct tagVARIANT  {
   VARTYPE vt;
   unsigned short wReserved1;
   unsigned short wReserved2;
   unsigned short wReserved3;
   union {
      Byte                    bVal;                 // VT_UI1.
      Short                   iVal;                 // VT_I2.
      long                    lVal;                 // VT_I4.
      float                   fltVal;               // VT_R4.
      double                  dblVal;               // VT_R8.
      VARIANT_BOOL            boolVal;              // VT_BOOL.
      SCODE                   scode;                // VT_ERROR.
      CY                      cyVal;                // VT_CY.
      DATE                    date;                 // VT_DATE.
      BSTR                    bstrVal;              // VT_BSTR.
      DECIMAL                 FAR* pdecVal          // VT_BYREF|VT_DECIMAL.
      IUnknown                FAR* punkVal;         // VT_UNKNOWN.
      IDispatch               FAR* pdispVal;        // VT_DISPATCH.
      SAFEARRAY               FAR* parray;          // VT_ARRAY|*.
      Byte                    FAR* pbVal;           // VT_BYREF|VT_UI1.
      short                   FAR* piVal;           // VT_BYREF|VT_I2.
      long                    FAR* plVal;           // VT_BYREF|VT_I4.
      float                   FAR* pfltVal;         // VT_BYREF|VT_R4.
      double                  FAR* pdblVal;         // VT_BYREF|VT_R8.
      VARIANT_BOOL            FAR* pboolVal;        // VT_BYREF|VT_BOOL.
      SCODE                   FAR* pscode;          // VT_BYREF|VT_ERROR.
      CY                      FAR* pcyVal;          // VT_BYREF|VT_CY.
      DATE                    FAR* pdate;           // VT_BYREF|VT_DATE.
      BSTR                    FAR* pbstrVal;        // VT_BYREF|VT_BSTR.
      IUnknown                FAR* FAR* ppunkVal;   // VT_BYREF|VT_UNKNOWN.
      IDispatch               FAR* FAR* ppdispVal;  // VT_BYREF|VT_DISPATCH.
      SAFEARRAY               FAR* FAR* pparray;    // VT_ARRAY|*.
      VARIANT                 FAR* pvarVal;         // VT_BYREF|VT_VARIANT.
      void                    FAR* byref;           // Generic ByRef.
      char                    cVal;                 // VT_I1.
      unsigned short          uiVal;                // VT_UI2.
      unsigned long           ulVal;                // VT_UI4.
      int                     intVal;               // VT_INT.
      unsigned int            uintVal;              // VT_UINT.
      char FAR *              pcVal;                // VT_BYREF|VT_I1.
      unsigned short FAR *    puiVal;               // VT_BYREF|VT_UI2.
      unsigned long FAR *     pulVal;               // VT_BYREF|VT_UI4.
      int FAR *               pintVal;              // VT_BYREF|VT_INT.
      unsigned int FAR *      puintVal;             //VT_BYREF|VT_UINT.
   };
};

Answer 2

一般来说是这个，myvariant.bstrVal你可以判断一下myvariant.vt == VT_BSTR 还是其他的值from msdn:
-------------------------------typedef struct FARSTRUCT tagVARIANT VARIANT;
typedef struct FARSTRUCT tagVARIANT VARIANTARG;typedef struct tagVARIANT  {
   VARTYPE vt;
   unsigned short wReserved1;
   unsigned short wReserved2;
   unsigned short wReserved3;
   union {
      Byte                    bVal;                 // VT_UI1.
      Short                   iVal;                 // VT_I2.
      long                    lVal;                 // VT_I4.
      float                   fltVal;               // VT_R4.
      double                  dblVal;               // VT_R8.
      VARIANT_BOOL            boolVal;              // VT_BOOL.
      SCODE                   scode;                // VT_ERROR.
      CY                      cyVal;                // VT_CY.
      DATE                    date;                 // VT_DATE.
      BSTR                    bstrVal;              // VT_BSTR.
      DECIMAL                 FAR* pdecVal          // VT_BYREF|VT_DECIMAL.
      IUnknown                FAR* punkVal;         // VT_UNKNOWN.
      IDispatch               FAR* pdispVal;        // VT_DISPATCH.
      SAFEARRAY               FAR* parray;          // VT_ARRAY|*.
      Byte                    FAR* pbVal;           // VT_BYREF|VT_UI1.
      short                   FAR* piVal;           // VT_BYREF|VT_I2.
      long                    FAR* plVal;           // VT_BYREF|VT_I4.
      float                   FAR* pfltVal;         // VT_BYREF|VT_R4.
      double                  FAR* pdblVal;         // VT_BYREF|VT_R8.
      VARIANT_BOOL            FAR* pboolVal;        // VT_BYREF|VT_BOOL.
      SCODE                   FAR* pscode;          // VT_BYREF|VT_ERROR.
      CY                      FAR* pcyVal;          // VT_BYREF|VT_CY.
      DATE                    FAR* pdate;           // VT_BYREF|VT_DATE.
      BSTR                    FAR* pbstrVal;        // VT_BYREF|VT_BSTR.
      IUnknown                FAR* FAR* ppunkVal;   // VT_BYREF|VT_UNKNOWN.
      IDispatch               FAR* FAR* ppdispVal;  // VT_BYREF|VT_DISPATCH.
      SAFEARRAY               FAR* FAR* pparray;    // VT_ARRAY|*.
      VARIANT                 FAR* pvarVal;         // VT_BYREF|VT_VARIANT.
      void                    FAR* byref;           // Generic ByRef.
      char                    cVal;                 // VT_I1.
      unsigned short          uiVal;                // VT_UI2.
      unsigned long           ulVal;                // VT_UI4.
      int                     intVal;               // VT_INT.
      unsigned int            uintVal;              // VT_UINT.
      char FAR *              pcVal;                // VT_BYREF|VT_I1.
      unsigned short FAR *    puiVal;               // VT_BYREF|VT_UI2.
      unsigned long FAR *     pulVal;               // VT_BYREF|VT_UI4.
      int FAR *               pintVal;              // VT_BYREF|VT_INT.
      unsigned int FAR *      puintVal;             //VT_BYREF|VT_UINT.
   };
};

Answer 3

看见了！
对了，阿飞兄，我一直想查看这个VARIANT结构，就是找不到，你是怎么找到的呀？教教老弟了！呵呵

Answer 4

这个论坛是有问题，提交完一个回复都没有，我就再提交，最后告诉wo
你不能连贴三次，ft
msdn索引里面输入VARIANT (别按回车)往下看n行， 有一条叫“VARIANT and VARIANTARG”，双击水边选一个看都可以了

Answer 5

myvariant.vt == VT_BSTR
这个判断不等呀，前者是9，后者是8
我的EXCEL文件里这是一个字符串“you”啊！
怎么回事呀？完整代码如下：
void CAutoprojectDlg::OnRun() 
{
  try
{
_Application app; // app is an _Application object.
_Workbook book; // More object declarations.
_Worksheet sheet;
Workbooks books;
Worksheets sheets;
Range range; // Used for Microsoft Excel 97 components.
LPDISPATCH lpDisp; // Often reused variable.
COleVariant
covTrue((short)TRUE),
covFalse((short)FALSE),
covOptional((long)DISP_E_PARAMNOTFOUND, VT_ERROR); if(!app.CreateDispatch("Excel.Application"))
{
AfxMessageBox("Couldn't CreateDispatch() for Excel");
return;
}
app.SetVisible(TRUE);
lpDisp = app.GetWorkbooks(); // Get an IDispatch pointer.
ASSERT(lpDisp);
books.AttachDispatch(lpDisp); // Attach the IDispatch pointer
// to the books object.
lpDisp = books.Open("E:\\test.xls", // test.xls is a workbook.
covOptional, covOptional, covOptional, covOptional, covOptional,
covOptional, covOptional, covOptional, covOptional, covOptional,
covOptional, covOptional ); // Return Workbook's IDispatch pointer.
book.AttachDispatch( lpDisp );
lpDisp = book.GetSheets();
ASSERT(lpDisp);
sheets.AttachDispatch(lpDisp);
// Get sheet #1 and attach the IDispatch pointer to your sheet
// object.
lpDisp = sheets.GetItem( COleVariant((short)(1)) ); 
ASSERT(lpDisp);
sheet.AttachDispatch(lpDisp); lpDisp = sheet.GetRange(COleVariant("B2"), COleVariant("B2"));
range.AttachDispatch(lpDisp);

VARIANT myvariant;
CString str;
bool is_str=false;
myvariant=range.GetItem(COleVariant((long)(1)),COleVariant((long)(1)));
if (myvariant.vt == VT_BSTR)
is_str=true;
    str=myvariant.bstrVal;
AfxMessageBox(str);// range.SetNumberFormat(COleVariant("@"));
// range.SetItem(COleVariant((long)(1)),COleVariant((long)(1)),COleVariant(LPCTSTR("000666"))); 
// Release dispatch pointers.
range.ReleaseDispatch();
sheet.ReleaseDispatch();
// This is not really necessary because
// the default second parameter of AttachDispatch releases
// when the current scope is lost. } // End of processing. catch(COleException *e)
{
char buf[1024]; // For the Try...Catch error message.
sprintf(buf, "COleException. SCODE: %08lx.", (long)e->m_sc);
::MessageBox(NULL, buf, "COleException", MB_SETFOREGROUND | MB_OK);
} catch(COleDispatchException *e)
{
char buf[1024]; // For the Try...Catch error message.
sprintf(buf,
"COleDispatchException. SCODE: %08lx, Description: \"%s\".",
(long)e->m_wCode,(LPSTR)e->m_strDescription.GetBuffer(512));
::MessageBox(NULL, buf, "COleDispatchException",
MB_SETFOREGROUND | MB_OK);
} catch(...)
{
::MessageBox(NULL, "General Exception caught.", "Catch-All",
MB_SETFOREGROUND | MB_OK);
} }

Answer 6

我以前做过该操作的冬冬我使用的方法是先判断该VARIANT内你要读取数据的类型
然后根据类型来使用变量读取 这个绝对错不了
判断一下吧 先

Answer 7

VariantChangeType(&s,&s,0,VT_BSTR)
就全是BSTR的了
不过你得判断是否为
VT_EMPTY
VT_NULL

Answer 8

myvariant=range.getValue();vt = 9 //VT_DISPATCH = 9, 你拿到的是一个item对象