Sorry for my beginner question, but since the course never covered this, how do I create a c++ code that have a variable that takes input from a txt file on my computer? Say I created a int named number, how do I set it to a specific value in existing txt file? And how do I make the code automatically update the txt file if “number” were to change? Thank you
#include <iostream>
#include <fstream>
using namespace std;
int main() {
string filePath = "example.txt";
ifstream inputFile;
inputFile.open(filePath);
ofstream outputFile;
outputFile.open (filePath);
string content = "";
inputFile >> content;
content += "World!";
outputFile << content;
inputFile.close();
outputFile.close();
return 0;
}
https://cplusplus.com/doc/tutorial/files/
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You read input by ifstream and output by ofstream. The example and link that I given should be enough self-explanatory.
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If you want to add integers or something like that you have to do a type-casting with stoi.
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I’m pretty sure no coding language available offers automatic file updating corresponding to variable (Correct me if I’m incorrect ty) since it is extremely resource-consuming. You have to do the file I/O everytime you have updates on variable.
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