Storing and accessing data from and to .txt files.

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    Storing and accessing data from and to .txt files.

    How would you store string data inside a .txt file, so you can request data from the .txt file that is already there, or store additional data?

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    C++ Witch laserlight's Avatar
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    That sounds very... generic. Have you learnt about what's in the <fstream> standard header?
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    Registered User hk_mp5kpdw's Avatar
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    Write the strings to the file, one per line would likely be best. When reading from the file, just store everything in a container of some sort, std::vector<std::string> for example.
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    Quote Originally Posted by hk_mp5kpdw View Post
    Write the strings to the file, one per line would likely be best. When reading from the file, just store everything in a container of some sort, std::vector<std::string> for example.
    Yes, the data in the application is stored in a vector. But how do you "extract" the data of a vector to a text file; AND still be able to make the app recognize it, and edit it later on?

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    C++ Witch laserlight's Avatar
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    But how do you "extract" the data of a vector to a text file; AND still be able to make the app recognize it, and edit it later on?
    You come up with a file format. For example, as mentioned by hk_mp5kpdw, each element of the vector could be on a single line. Then since your vector holds structs as elements, the members of the struct could be comma separated, or separated by pipes, or perhaps you have a fixed width to store them, etc.

    Actually, I would suggest using SQLite and coming up with a database schema instead of a custom file format, but that may be a little advanced at this point, unless you already have some knowledge of relational databases.
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    Quote Originally Posted by laserlight View Post
    You come up with a file format. For example, as mentioned by hk_mp5kpdw, each element of the vector could be on a single line. Then since your vector holds structs as elements, the members of the struct could be comma separated, or separated by pipes, or perhaps you have a fixed width to store them, etc.

    Actually, I would suggest using SQLite and coming up with a database schema instead of a custom file format, but that may be a little advanced at this point, unless you already have some knowledge of relational databases.
    Using the simplest .txt storage methods is a good start point, no? In case you want to help out, I'd love to understand it.

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    C++ Witch laserlight's Avatar
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    Using the simplest .txt storage methods is a good start point, no?
    If you want to learn about file handling, then yes. What do you already know?
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    Quote Originally Posted by laserlight View Post
    If you want to learn about file handling, then yes. What do you already know?
    I know that a header named "<fstream>" exists. And as I said, it dosent have to be very complex at the beginning stage of the learning process. Using the most easy way will do it for a starter.

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    C++ Witch laserlight's Avatar
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    Check out the tutorial on file I/O, and also check out cppreference.com's entries on C++ I/O.
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    Thanks

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