How to use a return value in another function in Javascript?

Question

I\'m self-teaching myself JavaScript and out of curiosity I\'m wondering what is the proper way of returning a value from one function to be used in another function. For ex

Answer 1

Call function within other function :

function abc(){    
    var a = firstFunction();    
}

function firstFunction() {
    Do something;
    return somevalue 
}

Answer 2

Call the function and save the return value of that very call.

function firstFunction() {
  // do something
  return "testing 123";
}

var test = firstFunction();  // this will grab you the return value from firstFunction();
alert(test);

You can make this call from another function too, as long as both functions have same scope.

For example:

function testCase() {
  var test = firstFunction(); 
  alert(test);
}

Demo

Answer 3

You could call firstFunction from secondFunction :

function secondFunction() {
    alert(firstFunction());
}

Or use a global variable to host the result of firstFunction :

var v = firstFunction();
function secondFunction() { alert(v); }

Or pass the result of firstFunction as a parameter to secondFunction :

function secondFunction(v) { alert(v); }
secondFunction(firstFunction());

Or pass firstFunction as a parameter to secondFunction :

function secondFunction(fn) { alert(fn()); }
secondFunction(firstFunction);

Here is a demo : http://jsfiddle.net/wared/RK6X7/.

Answer 4

To copy the return value of any javascript, we can use inbuilt copy() method.

you can use any expression, function, etc find some examples below

1. using expresseion

a = 245; copy(a);

2. using function

a = function() {
  return "Hello world!"
}
copy(a());

Official Doc for reference

Answer 5

You can do this for sure. Have a look below

function fnOne(){
  // do something
  return value;
}


function fnTwo(){
 var strVal= fnOne();
//use strValhere   
 alert(strVal);
}

Answer 6

var captcha = '';
//function name one
function one(captcha){
var captcha = captcha;
//call another function and pass variable data
var captcha = firstFunction(captcha); 
};
// second function name
function firstFunction(captcha){
alert(captcha);
}