std :: array和字节读取

Question

I have read a lot of things about not using C-style in C++, but instead use containers like std::array, std::vector or std::string.

Now I am trying to read and write small binary files with file streams and store it in std::array.

It looks like the read and write method from std::fstream can work only with C-style arrays...

So this is what I think about:

int main(int argc, char **argv)
{
    std::fstream testFile, outTestFile;
    testFile.open("D:/mc_svr/another/t/world/region/r.0.0.mca", std::fstream::in | std::fstream::binary);
    outTestFile.open("D:/mc_svr/another/t/world/region/xyz.xyz", std::fstream::out | std::fstream::binary);

    std::array<byte_t, 8192> testArray;

    testFile.read((char*) &testArray, 8192);
    outTestFile.write((char*) &testArray, 8192);

    testFile.close();
    outTestFile.close();

    return 0;
}

byte_t is just a

typedef char byte_t;

It works. But it is this the good way to do it ? If no, what are the other ways to do it ? Should I use byte_t [] instead ?

Answer 1

Use std::array::data :

testFile.read(testArray.data(), testArray.size());
outTestFile.write(testArray.data(), testArray.size());

Note the use of .size() instead of the magic number.

Also you don't need to .close() your files. The fstream destructor will do that for you.