Node.js Function Returns 'undefined'

Question

The following Node.js code prints 'undefined', even though it found the file.

var fileFound = function() {
    fs.readFile('public/images/acphotos/Friedrich-EL36N35B.jpg', function(err, data) {
          if (err) {
            console.log(err);
            return false;
          } else {
            return true;
        }
    });
}

console.log("Return value: " + fileFound());

How would I rewrite it? I don't fully understand the solution in the other thread I was shown.

Each function has it's own returned value. The `fileFound` function returns nothing that in JavaScript means _undefined_. — Ram, Aug 02 '16 at 20:37
you can pass a callback function when function is called and return a callback with a value from a called function — JN_newbie, Aug 09 '16 at 07:21

score 1 · Answer 1 · answered Aug 02 '16 at 20:37

1

Because the return statements are inside the callback passed into fs.readFile.

the fileFound function never returns anything, therefore you get undefined.

answered Aug 02 '16 at 20:37

Michele Ricciardi

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Node.js Function Returns 'undefined'

1 Answers1