How can CString be passed to format string %s?

Question

class MyString
{
public:
    MyString(const std::wstring& s2)
    {
        s = s2;
    }

    operator LPCWSTR() const
    {
        return s.c_str();
    }
pri         


        

Answer 1

CString is specifically designed such that it only contains a pointer that points to the string data in a buffer class. When passed by value to printf it will be treated as a pointer when seeing the "%s" in the format string.

It originally just happened to work with printf by chance, but this has later been kept as part of the class interface.

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This post is based on MS documentation long since retired, so I cannot link to their promise that they will continue to make this work.

However, before adding more downvotes please also read this blog post from someone sharing my old knowledge:

Big Brother helps you