I have a Javascript object like:
var my_object = { a:undefined, b:2, c:4, d:undefined };
How to remove all the undefined properties? False
You can simply chain _.omit() with _.isUndefined and _.isNull compositions, and get the result with lazy evaluation.
Demo
var result = _(my_object).omit(_.isUndefined).omit(_.isNull).value();
Update March 14, 2016:
As mentioned by dylants in the comment section, you should use the _.omitBy() function since it uses a predicate instead of a property. You should use this for lodash version 4.0.0 and above.
DEMO
var result = _(my_object).omitBy(_.isUndefined).omitBy(_.isNull).value();
Update June 1, 2016:
As commented by Max Truxa, lodash already provided an alternative _.isNil, which checks for both null and undefined:
var result = _.omitBy(my_object, _.isNil);