JS: var or not

using var or not, makes a difference!

by jmchen

JavaScript

"use strict";

// reference
// http://stackoverflow.com/questions/2485423/javascript-is-using-var-to-declare-variables-optional


external = 5;

function firsttry() {
  var external = 6;
  alert("first Try: " + external);
}

function secondtry() {
  external = 7;
  alert("second Try: " + external);
}

alert(external); // Prints 5
firsttry(); // Prints 6

alert(external); // Prints 5

secondtry(); // Prints 7
alert(external); // Prints 7