How to pass the value 'undefined' to a function with multiple parameters?

Question

I want to pass the value of \'undefined\' on a multiple parameter function but without omitting the parameter.

What do I mean with \"without omitting the paramet

Answer 1

You can use apply and an array of parameters to pass "undefined" as one of the parameters. For example, you wanted to pass parm1 as "undefined":

function myFunction (parm1, parm2) {

    if(typeof (parm1) === "undefined"){
        alert("parm1 is undefined")
    }

    if(typeof (parm2) === "undefined"){
        alert("parm2 is undefined")
    }

}

var myParameters = [undefined, "abc"];

myFunction.apply(valueForThis, myParameters );