javascript remove from object with undefined values code example

Example 1: js remove undefined from object

Object.keys(obj).forEach(key => obj[key] === undefined && delete obj[key])

Example 2: remove undefined from object js

const buildAnObjectFromAQuery = query => (
  {  
   ...query.foo && { foo: query.foo },  
   ...query.bar && { bar: query.bar },
  }
);