Borislav Hadzhiev
Wed Oct 13 2021·2 min read
Photo by Kamila Maciejewska
To remove all undefined values from an object:
Object.keys()
method to get an array of the object's keys.forEach()
method to iterate over the array and delete all
undefined
values using the delete
operator.const obj = { a: undefined, b: 'test', c: undefined, }; Object.keys(obj).forEach(key => { if (obj[key] === undefined) { delete obj[key]; } }); console.log(obj); // 👉️ {b: 'test'}
The Object.keys method returns an array containing the object's keys.
const obj = { a: undefined, b: 'test', c: undefined, }; // 👇️ ['a', 'b', 'c'] console.log(Object.keys(obj))
The Array.forEach method allows us to iterate over the array of keys.
We check if the value, associated to the current key is equal to undefined
and
if the condition is met, we use the
delete operator
to delete the key-value pair.
forEach
method is not supported in Internet Explorer. If you have to support the browser, use the next approach covered in this article.To remove all undefined values from an object:
for...in
loop to iterate over the object.undefined
and delete the
value if it satisfies the condition.// Supported in IE const obj = { a: undefined, b: 'test', c: undefined, }; for (const key in obj) { if (obj[key] === undefined) { delete obj[key]; } } console.log(obj); // 👉️ {b: 'test'}
The for...in loop allows us to iterate over the object's properties.
We check if the value of the current property is equal to undefined
and if
either condition is satisfied, we delete the key-value pair.