Stop breaking your code by accessing undefined value

I have written a utility funtion to get value from a object and if value is not present then it returns default value given by you.

eg:

var myObj = {
  a: {
    b: {
      c: 'c'
    }
  }
};

Now c value from above object
solution
console.log(myObj.a.b.c) //output 'c'

what if any property of myObj not available then it will break your code and user cant see anything.

My Solution to objects

const getValue = (obj, path, defaultValue) => {
    try{
        if(!(obj instanceof Array)){
            let myValue = obj;
            for(let key of path){
                if(!(key in myValue)){
                    return defaultValue;
                }else{
                    myValue = myValue[key];
                }
            }
            return myValue;
        }
    }catch(error){
        console.log({ error });
        return defaultValue;
    }
}

use getValue function to get either right value or user given default value

getValue(myObj, ["a", "b", "c"], null);

if c value available then it will return c value else it will return null

getValue(object, path_to_property, user_default_value)

Above Solution will work with all older and newer browsers

Another Simplest solution to the problem is modern es6 syntax

lets use same example

var myObj = {
  a: {
    b: {
      c: 'c'
    }
  }
};

if i try to access something which is not present within the object

myObj.a.p //output undefined

if i try to complicate things a little more

myObj.a.p.b

VM250:1 Uncaught TypeError: Cannot read properties of undefined (reading 'b')
    at <anonymous>:1:9

p is undefined and now i am trying to access a property of undefined got error boom

Modern Solution to the problem which will work with all modern browsers

myObj?.a?.p?.b || 'b' //output b