Shorthand if/else statement Javascript
var x = y !== undefined ? y : 1;
Note that var x = y || 1;
would assign 1
for any case where y
is falsy (e.g. false
, 0
, ""
), which may be why it "didn't work" for you. Also, if y
is a global variable, if it's truly not defined you may run into an error unless you access it as window.y
.
As vol7ron suggests in the comments, you can also use typeof
to avoid the need to refer to global vars as window.<name>
:
var x = typeof y != "undefined" ? y : 1;
Another way to write it shortly
bePlanVar = !!((bePlanVar == false));
// is equivalent to
bePlanVar = (bePlanVar == false) ? true : false;
// and
if (bePlanVar == false) {
bePlanVar = true;
} else {
bePlanVar = false;
}