Converting File Data Into Double

This is a discussion on Converting File Data Into Double within the C++ Programming forums, part of the General Programming Boards category; I am using files to store some numbers in my program. I am storing a string on one line and ...

  1. #1
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    Converting File Data Into Double

    I am using files to store some numbers in my program. I am storing a string on one line and then a number on another and it repeats (so i've got a client/number sort of system). I can use getline to get that information out of the file but I can't use the number. I need to be able to perform addition and subtraction on the numer... how can I do this?

    Also, is there a way to edit a specific part of a file (ie. alter the number and leave the rest as is?).

    I am using Borland C++ Builder 5:

    Thanks for any help you can provide -
    retretret

  2. #2
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    Read every other line into a double rather than a string.

    //get text
    in.getline(text,sizeof(text));
    //get double
    in >> d;

    >Also, is there a way to edit a specific part of a file (ie. alter the number and leave the rest as is?).

    You could read the whole file into an array of string/double structs, change the ones you want and then write them all back out to file.

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