仅读取二进制文件的第一行

Question

Functions should create Complex (my structure) vector, than save it to binary file and than read it from binary file. The problem is that it reads good only first line.

The structure is good. Everything besides reading is working well. These are read and write functions:

void saveVectorBin(vector<Complex> &v, const string filename) {
    ofstream output;
    output.open(filename, ios::binary);
    if (output)
    {
        for (auto i: v) {
            output.write(reinterpret_cast<char*> (&i), sizeof(i));
            output << endl;
        }
        cout << "Wektor zapisany do pliku " << filename << endl;
        output.close();
    }
    else cout << endl << "BLAD TWORZENIA PLIKU BIN" << endl;
}

vector<Complex> readComplexVectorBin(const string &filename) {
    vector<Complex> v;
    ifstream input;
    input.open(filename, ifstream::binary);
    if (input) {
        Complex line;
        while (input.read(reinterpret_cast<char*> (&line), sizeof(Complex))) {
            v.push_back(Complex(line));
        }
        input.close();
    }
    else cout << endl << "BLAD ODCZYTU PLIKU" << endl;
    return v;
}

Should show:

26.697 + 7.709i
20.133 + 23.064i
9.749 + 8.77i 

Instead it shows:

26.697 + 7.709i
1.43761e-57 + 1.83671e-43i
1.26962e+306 + -2.39343e-259i

Answer 1

Your issue is that you are inserting a newline into a binary file.

output << endl;

adds data to your file that

while (input.read(reinterpret_cast<char*> (&line), sizeof(Complex))) {
    v.push_back(Complex(line));
}

fails to take into consideration. You either need to get rid of output << endl; in your writing loop (easiest solution) or read in and discard the newline in your reading loop (hardest solution).