const obj = {
c: null,
name: 'Ben',
age: 40,
a: undefined,
work_in: 'JavaScript',
b: undefined,
};
Object.keys(obj).forEach(key => {
if (obj[key] === null || obj[key] === undefined) {
delete obj[key];
}
});
console.log(obj);
/*
run:
{
age: 40,
name: "Ben",
work_in: "JavaScript"
}
*/