CODEWITHSUNDEEP
c++typesbinary
umayfindurself
umayfindurself

Reputation: 131

modify typedef declaration within if..else

The problem that I am trying to solve:

Read a binary file and write the contents to a text file. The format of the contents within the binary file are specified by the user using an option, e.g. bin2txt.exe [filename] [/f], where /f denotes the contents in the binary file are of float type.

My current algorithm:

declare:

typedef int datatype;

Use if...else or switch...case to modify datatype to float, unsigned int short etc. within the main code.

The problem:

datatype is successfully modified within the if...else, but switches back to default (here, int) outside the if...else/switch...case. This means, I could read binary to a vector then write the vector to a text file within the if...else statements. But this way, the code becomes too repetitive (every if block will have a vector declaration, initialization, reading into vector and writing to text file.). It would be better to avoid such repetition.

Could someone please guide me to the write direction. ? Thanks.

Upvotes: 0

Views: 1293

Answers (1)

molbdnilo
molbdnilo

Reputation: 66441

If you find yourself writing identical code except for the types involved, it's often a good candidate for a template.

A simple (untested) variant with no error checking or input verification:

template<typename T>
void convert(std::istream& in, std::ostream& out)
{
    T data;
    while (in.get(reinterpret_cast<char*>(&data), sizeof(data)))
    {
        out << data << std::endl;
    }
}

int main(int argc, char* argv[])
{
    std::ifstream input(argv[1], std::ios::binary);
    std::ostream& output = std::cout;
    std::string format = argv[2];
    if (format == "/f")
    {
        convert<float>(input, output);
    }
    else
    {
        convert<int>(input, output);
    }
}

Upvotes: 2

Related Questions