字符串： 怎样在ANSI 和 UNICODE间做转换

问题: 怎样在ANSI 和 UNICODE间做转换？
答案:
这个答案启发自 Yves M贴出的一张回复（reply）

ANSI 到 UNICODE:

这个转换用函数MultiByteToWideChar()完成
代码:
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char *ansistr = "Hello";
int a = lstrlenA(ansistr)+1;
BSTR unicodestr = SysAllocStringLen(NULL, 2*a);
MultiByteToWideChar(CP_ACP, 0, ansistr, a, unicodestr, a);
AfxMessageBox(CString(unicodestr), MB_OK, 0); //displays "Hello"
//... when done, free the BSTR
SysFreeString(unicodestr);
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UNICODE 到 ANSI:
UNICODE大多数情况下被OLE函数返回， 像这个
代码:
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HRESULT SomeOLEFunction(BSTR &bstr)
{
bstr = ::SysAllocString(L"Hello");
return S_OK;
}
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这个转换用WideCharToMultiByte()函数完成
代码:
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BSTR unicodestr;
SomeOLEFunction(unicodestr);
int a = SysStringLen(unicodestr)+1;
char *ansistr = new char[a];
WideCharToMultiByte(CP_ACP,
0,
unicodestr,
-1,
ansistr,
a,
NULL,
NULL);
AfxMessageBox(ansistr, MB_OK, 0); // will display "Hello"
//...use the strings, then free their memory:
delete[] ansistr;
SysFreeString(unicodestr);
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