Question

I am well aware of techniques to convert CString to a C-style character. One of them is to use strcpy/_tcscpy, and others include using CStrBuf.

The problem:

char Destination[100];
CStringA Source; // A is for simplicity and explicit ANSI specification.

Source = "This is source string."

Now I want this:

Destination = Source;

To happen automatically. Well, that logically means writing a conversion operator in CString class. But, as implicit as it is, I dont have privileges to change the CString class.

I thought of writing a global conversion opertor and global assignment operator. But it doesnt work:

operator char* (const CStringA&); // Error - At least must be class-type
operator = ... // Won't work either - cannot be global.

Yes, it is definitely possible to write function (preferably a templated one). But that involves calling the function, and it is not smooth as assignment operator.

Answer 1

Well, I don’t want to say that this is in any way recommendable, but you could hijack some lesser-used operator for a quick hack:

void operator<<=(char * dst, const std::string & s)
{
  std::strcpy(dst, s.c_str());
}

int main()
{
  char buf[100];
  std::string s = "Hello";

  buf <<= s;
}

You could even rig up a moderately safe templated version for statically sized arrays:

template <typename TChar, unsigned int N>
inline void operator<<=(TChar (&dst)[N], const std::string & s)
{
  std::strncpy(dst, s.c_str(), N);
}