Question

I don’t know what is the best way to write it and how to… I have a function like

function myFunc(myVal1, myVal2){/*... various things ...*/};

where myVal1 and myVal2 are numbers

Sometimes I want to be able to recall the function passing only one parameter just by calling myFunc(myVal1). Doing so I want that myVal2 would have a standard value, if not declared, of 0.

I was thinking to write something

function myFunc(myVal1, myVal2){
    if(myVal2 == NaN)
         myVal2 = 0;
    }
}

But I don’t believe that it is the right way to do it.
Thx very much for the help!

Answer 1

Arguments that are not set have type undefined, test for it like this.

function myFunc(myVal1, myVal2){ 
    if(typeof myVal2 == "undefined") 
         myVal2 = 0; 
    //the rest of the function goes here
}