Simple data serialization example using C++ with only standard library

When to use

This example serve as an inspiration in case you want to write an array of variable size of structures into a binary file and later read them. Like a vector of structs that has string members, as follows.

struct Data {
    std::string str;
    int value;
};

std::vector<Data> myCompicatedData;

Usage

Use ofstream to write your data then open it with an ifstream. Writing and reading depends on the type of the data:

• For binary data (like double or float) use the std::ofstream::write method
• For plain data (like bool, int, uint32_t) use the operator<<
• For writing std::string use the operator<< followed by a delimiter character, and read using the getline method

Constrains

1. You must define a char that will be the delimiter, and under no circumstances present in the string member
2. Maximum length of one string must be defined
3. The structure should not end with the string

Consequences

It is not possible to write to binary then read structures only containing string members (constraint #3).
Writing data from raw user input is not recommended as it
a) might contain the delimiter (constraint #1) b) might be 'infinite' long (constraint #2) therefore invalidating the read.