JS —How to reset all values in a Javascript object

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There are many ways to “reset” an object’s value in JavaScript. In this article, I will show you my approach to this case.

1. Default Object (not elegant)

let item = {
    discount : true,
    percentage : false,
    qty : true,
    unit_price : false,
    estimated_cost : true,
    description_cost: false,
};
let defaultItem = {
    discount : false,
    percentage : false,
    qty : false,
    unit_price : false,
    estimated_cost : false,
    description_cost: false,
};
item = {...defaultItem}

2. Loop Object (more elegant)

let item = {
    discount : true,
    percentage : false,
    qty : true,
    unit_price : false,
    estimated_cost : true,
    description_cost: false,
};
item = Object.keys(item).reduce((acc, curr) => ({...acc, [curr]: false}), {});

Extra: Loop Object with type check

Object.keys(fields).reduce((acc, curr) => {
  if (fields[curr] === null) return { ...acc, [curr]: null };
  if (typeof fields[curr] === 'undefined') return { ...acc, [curr]: undefined };
  if (typeof fields[curr] === 'boolean') return { ...acc, [curr]: false };
  if (typeof fields[curr] === 'string') return {...acc, [curr]: ''};
  if (typeof fields[curr] === 'number') return {...acc, [curr]: 0};
  if (fields[curr] instanceof Array) return { ...acc, [curr]: [] };
  if (typeof fields[curr] === 'object') return { ...acc, [curr]: {} };
}, {})