Read and write a text file in typescript

Question

How should I read and write a text file from typescript in node.js? I am not sure would read/write a file be sandboxed in node.js, if not, i believe there should be a way i

Answer 1

First you will need to install node definitions for Typescript. You can find the definitions file here:

https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/node/node.d.ts

Once you've got file, just add the reference to your .ts file like this:

///

Then you can code your typescript class that read/writes, using the Node File System module. Your typescript class myClass.ts can look like this:

/// 

class MyClass {

    // Here we import the File System module of node
    private fs = require('fs');

    constructor() { }

    createFile() {

        this.fs.writeFile('file.txt', 'I am cool!',  function(err) {
            if (err) {
                return console.error(err);
            }
            console.log("File created!");
        });
    }

    showFile() {

        this.fs.readFile('file.txt', function (err, data) {
            if (err) {
                return console.error(err);
            }
            console.log("Asynchronous read: " + data.toString());
        });
    }
}

// Usage
// var obj = new MyClass();
// obj.createFile();
// obj.showFile();

Once you transpile your .ts file to a javascript (check out here if you don't know how to do it), you can run your javascript file with node and let the magic work:

> node myClass.js