1. LPCTSTR == const TCHAR*
LPTSTR lstrcpy(LPTSTR lpString1,LPCTSTR lpString2);
2. wcslen(TCHAR* s) 取宽字符的长度
CString str = _T("中国人");
TCHAR* pChar = str.GetBuffer(0);
int m = sizeof(pChar); // == 4
int n = wcslen(pChar); // == 3
int x = sizeof(str); // == 4
int y = wcslen(str); // == 3
int xx= str.GetLength(); // == 3
3. strlen(char *s) 取字符串的长度