Feb 24, 2016 · for (var i in obj) { if (obj[i] === null || obj[i] === undefined) { delete obj[i]; } return obj; This is the actual question: Make a function that takes in an object, loops through all its properties, and removes any that are falsy. Then return the object that was passed in. (hint: delete)

Jun 1, 2015 · To remove those properties you can use this algorithm: for (k in myObj) { if (myObj.hasOwnProperty(k) && myObj[k] === false) { delete myObj[k]; } } If you are just interested in the keys of non-false values, you can use: var keys = Object.keys(myObj).filter(function (k) { return myObj[k] !== false; });

Feb 7, 2018 · The answer to "can I do x to an object" (or an array for that matter) is usually "yes" and it frequently involves some form of reduce. If you want to filter falsy values you could do something like this:

Apr 8, 2021 · Sometimes we want to remove null, empty, undefined, false value attribute from an object. we can do this using the below method. const removeFalsyElement = object => { const newObject = {}; Object.keys(object).forEach(key => { if (object[key]) { newObject[key] = object[key]; } }); return newObject; };

Mar 3, 2025 · Write a JavaScript program to remove all false values from an object or array. Use recursion. Initialize the iterable data, using Array.isArray(), Array.prototype.filter() and Boolean for arrays in order to avoid sparse arrays.

Jun 5, 2024 · Using Array.prototype.flatMap(), you can remove falsy values by mapping each element to an array containing the element if it’s truthy, or an empty array if it’s falsy. The resulting arrays are then flattened into a single array of truthy values.

To deeply remove all falsy values from an object or array, use the following algorithm: Use recursion to call the compactObject() function on each nested object or array. Initialize the iterable data using Array.isArray() , Array.prototype.filter() , and Boolean() .

May 10, 2016 · This method iterates over an object and removes all keys with falsy values. That is, falsy values will cause the key/value pair to be removed from the object. This is very useful for removing unwanted data from an object.

Oct 12, 2020 · Learn how to iterate over an object in JavaScript and remove properties with false values. Step-by-step guide with examples.

Jul 1, 2015 · When you use for-in, the iteration variable is set to the property name, not the value (it's not like PHP foreach). You need to use user[prop] to get the value. Also, you should return after the entire loop -- you're returning as soon as you find a truthy property.