Update object array without adding new properties from another object

Question

Is it possible to update only the existing property values of an object without adding new properties from another object?

Here is my example.

form = {name: '',email: ''};
data = {name: 'sample', email: 'sample@gmail.com', datofbirth: '6/2/1990' };

form = {...form, ...data};

console.log(form);

Result:

{"name":"sample","email":"sample@gmail.com","datofbirth":"6/2/1990"}

Expected Result:

{"name":"sample","email":"sample@gmail.com"}

I dont want the dateofbirth or any new property added on my form object.

Answer 1

Not sure this is what you want, hope it helps

const form = { name: '', email: '' };
const data = {
    name: 'sample',
    email: 'sample@gmail.com',
    datofbirth: '6/2/1990',
};
Object.keys(form).forEach(key => {
    if (data.hasOwnProperty(key)) {
        form[key] = data[key];
    }
});
console.log(form);

Answer 2

Only add the keys you want in the spread rather than the whole object

form = { ...form, name: data.name, email: data.email };

Answer 3

Iterate over all the keys in form and generate a new object using Object.assign and spread syntax.

const form = {name: '',email: ''},
      data = {name: 'sample', email: 'sample@gmail.com', datofbirth: '6/2/1990' },
      result = Object.assign(...Object.keys(form).map(k => ({[k] : data[k]})));
console.log(result);