Why do I make “use of deleted” function when passing a std::ofstream as parameter? [duplicate]

问题

I have a member that is std::ofstream fBinaryFile and a

void setFile( std::ofstream& pBinaryFile ) 
{
    fBinaryFile = pBinaryFile;
}

output:

 Data.h:86:16: error: use of deleted function ‘std::basic_ofstream<char>& std::basic_ofstream<char>::operator=(const
 std::basic_ofstream<char>&)’
     fBinaryFile = pBinaryFile;
                 ^

I understood that copy in std::ofstream is not allowed and maybe I'm missing something. Is possible save the content of pBinaryFile in fBinaryfile?

回答1:

Because the relevant operator is declared as

ofstream& operator= (const ofstream&) = delete;

which means it is explicitly prohibited so ofstream semantics does to support copying.

Depending on your architecture you can store a pointer/reference or move it.

回答2:

If you want to copy the content of pBinaryFile to fBinaryFile you need to declare pBinaryfile as an ifstream (input file stream), not an ofstream (output file stream) It should look something like this:

std::ifstream pBinaryFile;
std::ofstream fBinaryFile;
std::stringstream sstream;
std::string line
pBinaryFile.open(pBinaryFileName.c_str());
fBinaryFile.open(fBinaryFileName.c_str());
if (pBinaryFile.isopen()) {
    while (pBinaryFile.good()) {
        getline(pBinaryFile, line);
        fBinaryFile << sstream(line) << endl;
    }
}
pBinaryFile.close();
fBinaryFile.close();

Note that pBinaryFileName and fBinaryFileName refer to the paths of your files.

There might be mistakes in this code, but I think the solution looks similar to this.

I suggest this for further reading:

http://www.cplusplus.com/doc/tutorial/files/

来源：https://stackoverflow.com/questions/31674353/why-do-i-make-use-of-deleted-function-when-passing-a-stdofstream-as-paramete

标签

c++

ofstream