const obj = {
name: 'Roy',
x: undefined,
age: 60,
y: undefined,
work_in: 'TypeScript',
};
Object.keys(obj).forEach(key => {
if (obj[key] === undefined) {
delete obj[key];
}
});
console.log(obj);
/*
run:
{
"name": "Roy",
"age": 60,
"work_in": "TypeScript"
}
*/