[removed] The prettiest way to compare one value against multiple values [duplicate]

Answer 1

The switch method (as mentioned by Guffa) works very nicely indeed. However, the default warning settings in most linters will alert you about the use of fall-through. It's one of the main reasons I use switches at all, so I pretty much ignore this warning, but you should be aware that the using the fall-through feature of the switch statement can be tricky. In cases like this, though - I'd go for it.

Answer 2

What i use to do, is put those multiple values in an array like

var options = [foo, bar];

and then, use indexOf()

if(options.indexOf(foobar) > -1){
   //do something
}

for prettiness:

if([foo, bar].indexOf(foobar) +1){
   //you can't get any more pretty than this :)
}

and for the older browsers:
( https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/IndexOf )

if (!Array.prototype.indexOf) {
    Array.prototype.indexOf = function (searchElement /*, fromIndex */ ) {
        "use strict";
        if (this == null) {
            throw new TypeError();
        }
        var t = Object(this);
        var len = t.length >>> 0;
        if (len === 0) {
            return -1;
        }
        var n = 0;
        if (arguments.length > 0) {
            n = Number(arguments[1]);
            if (n != n) { // shortcut for verifying if it's NaN
                n = 0;
            } else if (n != 0 && n != Infinity && n != -Infinity) {
                n = (n > 0 || -1) * Math.floor(Math.abs(n));
            }
        }
        if (n >= len) {
            return -1;
        }
        var k = n >= 0 ? n : Math.max(len - Math.abs(n), 0);
        for (; k < len; k++) {
            if (k in t && t[k] === searchElement) {
                return k;
            }
        }
        return -1;
    }
}

Answer 3

Since nobody has added the obvious solution yet which works fine for two comparisons, I'll offer it:

if (foobar === foo || foobar === bar) {
     //do something
}

And, if you have lots of values (perhaps hundreds or thousands), then I'd suggest making a Set as this makes very clean and simple comparison code and it's fast at runtime:

// pre-construct the Set
var tSet = new Set(["foo", "bar", "test1", "test2", "test3", ...]);

// test the Set at runtime
if (tSet.has(foobar)) {
    // do something
}

For pre-ES6, you can get a Set polyfill of which there are many. One is described in this other answer.

Answer 4

Just for kicks, since this Q&A does seem to be about syntax microanalysis, a tiny tiny modification of André Alçada Padez's suggestion(s):

(and of course accounting for the pre-IE9 shim/shiv/polyfill he's included)

if (~[foo, bar].indexOf(foobar)) {
    // pretty
}

Answer 5

Why not using indexOf from array like bellow?

if ([foo, bar].indexOf(foobar) !== -1) {
    // do something
}

Just plain Javascript, no frameworks or libraries but it will not work on IE < 9.

Answer 6

(foobar == foo || foobar == bar) otherwise if you are comparing expressions based only on a single integer, enumerated value, or String object you can use switch. See The switch Statement. You can also use the method suggested by André Alçada Padez. Ultimately what you select will need to depend on the details of what you are doing.