Question

Possible Duplicate:
In Javascript, what does it mean when there is a logical operator in a variable declaration?

Stumbled across this code online, have no idea what it does, wasn’t able to find out with FireBug either, and I can’t google it because of the special characters…

var myValue = myInput.value || 0;

Answer 1

if myInput.value is undefined (or another falsy value) then the default value of 0 will be set

some examples…

myInput.value = undefined
var myValue = myInput.value || 0;
// myValue = 0

myInput.value = 10
var myValue = myInput.value || 0;
// myValue = 10