Question

我尝试了几种不同的方法来连接两个BSTR，并且还没有找到一种gopd方法。我根本没有在网上找到任何东西。

Answer 1

您应该使用像ATL CComBSTR这样的包装器来处理资源管理。

如果没有包装器，你可以这样做：

BSTR Concat(BSTR a, BSTR b)
{
    auto lengthA = SysStringLen(a);
    auto lengthB = SysStringLen(b);

    auto result = SysAllocStringLen(NULL, lengthA + lengthB);

    memcpy(result, a, lengthA * sizeof(OLECHAR));
    memcpy(result + lengthA, b, lengthB * sizeof(OLECHAR));

    result[lengthA + lengthB] = 0;
    return result;
}

int main()
{
    auto a = SysAllocString(L"AAA");
    auto b = SysAllocString(L"BBB");
    auto c = Concat(a, b);
    std::wcout << a << " + " << b << " = " << c << "\n";

    SysFreeString(a);
    SysFreeString(b);
    SysFreeString(c);
}

Answer 2

您可以使用_bstr_t包装器：

#include <comutil.h>

#pragma comment(lib, "comsupp.lib")

// you have two BSTR's ...
BSTR pOne = SysAllocString(L"This is a ");
BSTR pTwo = SysAllocString(L"long string");

// you can wrap with _bstr_t
_bstr_t pWrapOne = pOne;
_bstr_t pWrapTwo = pTwo;

// then just concatenate like this
_bstr_t pConcat =  pWrapOne + pWrapTwo;

连接两个BSTR的最佳方法是什么？

2 个答案: