描述:
我现在有一个ActiveX控件，我要从一个控件中导出一个特别大的数组该怎么做？（不用文件方式，是直接用内存导出！）
请各位大侠指教。 谢谢！
解决方案1:
VARIANT myVar;
myVar.vt = VT_CY;
// put 15.15 into the currency variant.
CURRENCY myValue;
myValue.Hi = 0;
myValue.Lo = (LONG)(15*10000 + 1537); // set the value to $15.15;
myVar.cyVal = myValue;
//or
myValue.int64 = (151234);
myVar.cyVal = myValue;
//Now get the value from a float and put it into the currency.
float myMoney = (float)5.37;
myVar.vt = VT_R4;
myVar.fltVal = myMoney;
//no loss of precission.
VariantChangeType(&myVar, &myVar, 0, VT_CY);
//Now get the value from a String
USES_CONVERSION;
myVar.bstrVal = SysAllocString(L"23.4345");
myVar.vt = VT_BSTR;
VariantChangeType(&myVar, &myVar, 0, VT_CY);
//Finally output a currency to a string.
myVar.cyVal.int64 += myVar.cyVal.int64; // + myVar.cyVal;
VariantChangeType(&myVar, &myVar, 0, VT_BSTR);
}
void CVarUseDlg::OnStrings()
{
//Create a BSTR and assign it to a Variant
BSTR x = SysAllocString(L"Hello");
VARIANT myVariant;
myVariant.vt = VT_BSTR;
myVariant.bstrVal = x;
SysFreeString(x);
//Create a CString and change it to a variant;
CString myCString(_T("My String"));
CString mySecondString;
//This is required to use the T2COLE macro.
USES_CONVERSION;
BSTR y = SysAllocString(T2COLE(myCString));
myVariant.bstrVal = y;
mySecondString = y;
SysFreeString(y);
_bstr_t str2="hjljljl";
char *str1 = (char*)str2;//char*是_bstr_t类的一个重载
CString str3=str1;
//Create two BSTRs and add them.
BSTR a = SysAllocString(L"One two ");
BSTR b = SysAllocString(L"three four.");
_bstr_t my_bstr_t(a, TRUE);
my_bstr_t += b;
myVariant.bstrVal = my_bstr_t;
// or
myVariant.bstrVal = _bstr_t(a, FALSE) + b;
//Change a bstr to a CString.
CString ANewString(b);
//or if CString already exists.
myCString = b;
//Use of CComBSTR
CComBSTR myCComBSTR(L"Hello");
myCComBSTR.Append(L", how are you?");
VARIANT varFromCCom;
varFromCCom.vt = VT_BSTR;
varFromCCom.bstrVal = myCComBSTR;
}
void CVarUseDlg::OnBasic()
{
//create a variant of the character 'c'
VARIANT varC;
varC.vt=VT_UI1;
varC.cVal = 'c';
//create a variant of the short 12
VARIANT varS;
varS.vt = VT_I2;
varS.iVal = 12;
//create a variant of the long 1234567;
VARIANT varL;
varL.vt = VT_I4;
varL.lVal = 1234567;
}
void CVarUseDlg::OnSafeArray()
{
//Create a standard array;
int* pMyOriginalArray = new int[100];
for(int count = 0; count < 100; count++) pMyOriginalArray[count] = count;
//Now get ready to put it into a safe array
HRESULT hr;
//create an array bound
SAFEARRAYBOUND rgsabound[1];
rgsabound[0].lLbound = 0; //The first (and only) collumn of our array starts at 0.
rgsabound[0].cElements = 100; //and has 100 elements.
//create the array
SAFEARRAY FAR* pMySafeArray;
pMySafeArray = SafeArrayCreate(VT_UI1, 1, rgsabound); //create the array of 4byte integers, one dimension
//with the bounds stored in rgsabound.
//now access the safe array's data.
int* pData;
hr = SafeArrayAccessData( pMySafeArray, (void**)&pData); //Get a pointer to the data.
//copy the 400 bytes of data from our old array to the new one.
memcpy(pData, pMyOriginalArray, 400);
//here we verify to you that the data is correct.
for(count = 0; count < 100; count++) ASSERT(pData[count] == pMyOriginalArray[count]);
SafeArrayUnaccessData(pMySafeArray);
VARIANT myVariant;
myVariant.parray = pMySafeArray;
myVariant.vt = VT_ARRAY|VT_UI1; // state it's an array and what type it holds.
//To put the SafeArray in a Variant
//pass the Variant to a function call.
FunctionCallWithVariant(myVariant);