Objects and I/O

Objects can be written to files and be read from files. Text files are a common means of sharing data between different programs. In Bitburner, you use the function ns.read() to read from a text file. Use the function ns.write() to write to a text file. The script below writes an object to file. The script then reads the object from file and compares the read object with the original object.

object-io.js

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/**
 * Write an object to file.  Read object from file.
 *
 * @param {NS} ns The Netscript API.
 */
export async function main(ns) {
    // Sam's profile as an object.
    const sam = {
        name: "Sam McPherson",
        age: 27,
        like: "sushi",
        dislike: "spinach",
    };

    const file = "sam.txt";
    const writeMode = "w";
    ns.write(file, JSON.stringify(sam), writeMode);
    const samobj = JSON.parse(ns.read(file));

    // Compare the read object with the original object.
    ns.tprintf(`Same name? ${sam.name === samobj.name}`);
    ns.tprintf(`Same age? ${sam.age === samobj.age}`);
    ns.tprintf(`Same like? ${sam.like === samobj.like}`);
    ns.tprintf(`Same dislike? ${sam.dislike === samobj.dislike}`);
}

The above script uses the method JSON.stringify() to first convert an object to its string representation, then writes the string to file. After reading the string representation from file, the script uses the method JSON.parse() to convert the string representation to an object. As you can see, JSON.stringify() and ns.write() can be used together to save an object to file, whereas JSON.parse() and ns.read() allow you to read an object from file.