Function to check Null

Question

I created a function in Javascript but something should be wrong cause i haven't the awaiting result. The idea is to test several variable. In case they are null i would replace with a blanck space. Here is my code :

function chkNull(myObject) { 
   if (myObject == null){
       myObject = " ";
   }
}

And below i test with this :

var dOb = null;
chkNull(dOb);

I don't know what is wrong. If i test with if dOb == null below the var declaration, it is working.

Reassigning the value of the *function parameter* does not change the passed in argument. — VLAZ, Dec 31 '19 at 16:49
I'm sorry, but this is in no way a duplicate question. Just because another question is relevant, even if it's the cause of the problem, doesn't mean they're both doing the same thing. — Brandon Dyer, Dec 31 '19 at 17:08

Brandon Dyer · Accepted Answer · 2019-12-31T17:13:32.080

2

You need to return a value

function checkNull(value) {
    if (value == null) {
        return " ";
    } else {
        return value;
    }
}

And using it:

let notNull = checkNull(maybeNull);

With your example:

let dOb = null;
dob = checkNull(dOb);

edited Dec 31 '19 at 17:13

answered Dec 31 '19 at 16:52

Brandon Dyer

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Function to check Null

1 Answers1