Visual C ++从文件中保存/读取多个变量

Question

This is my first post and I'm fairly new to C++. I am currently looking for a way to save multiple variables to a file (XML or TXT) so it looks like this:

charactername:George
level:5

I would also like to be able to read these and put them into a variable.

Ex:

std::string characterName = "George";

(but it would read George from the line in the file charactername:George)

I have a total of 68 variables (48 strings, 11 ints, and 9 bools) I want in 1 file.

Does anyone know a way to do this or a tutorial they could point me towards? I have found was to save 1 string to a file, but not multiple variables of different types.

Answer 1

I think you should learn how to use a datafile matrix,

But before that here is some basic file management code for you to try use, you'll be able to read in data and recover it based on a structured layout, when recovering your bool data use an implicit conversion to change from a string.

Here are some basic file operations, this will create a txt file that has data on new lines:

    // basic file operations
    // writing on a text file
    #include <iostream>
    #include <fstream>
    using namespace std;

    int main () {
      ofstream myfile ("example.txt");
      if (myfile.is_open())
      {
        myfile << "This is a line.\n";
        myfile << "This is another line.\n";  // this will for data onto a new line to be read later.
        myfile.close();
      }
      else cout << "Unable to open file";
      return 0;
    }

How to recover data, this will put the data into a string array which you can then use to recall data from in your code:

    // how to retrieve the data:
    #include <iostream>
    #include <fstream>
    #include <string>
    using namespace std;

    int main () {

      string line, data_array[67];
      ifstream myfile ("example.txt");
      if (myfile.is_open())
      {
        while ( getline (myfile,line) )
        {
           data_array[i] = line; i++;
        }
        myfile.close();
      }

      else cout << "Unable to open file"; 

      return 0;
    }

How to edit data, you'll need to have a function to read in all your variables and rewrite the whole text file as unless each line is exactly the same byte you can not jump directly to it.

To look more into detail you should learn how to use a datafile matrix, here are some nice videos to get you started.:

C++ Tutorial (Reading Rows and Columns from datafile Matrix

Matrix in C++ | Part #1 | simple matrix definition using arrays