Changing Date Copied From An Object

I am trying to copy a date property from an object and modify it as shown below, yet each time I try to modify the 'copied' date property, I end up having the object date property

Solution 1:

As @yBrodsky mentioned use new Date object and modify that one:

For example, you could do something like:

let currentTaskEndDate = new Date(taskObject.endDate);
currentTaskEndDate.setDate(currentTaskEndDate.getDate() + 5);

Solution 2:

Use new Date(taskObject.endDate) to create a copy of the date before you modify it:

const origDate = new Date(2017, 3, 13, 16, 46, 2);

const taskObject = {
  name: 'test',
  endDate: origDate,
};

console.log('taskObject:', taskObject);

// Copy the original Date object before modifying it
const currentTaskEndDateCopy = new Date(taskObject.endDate);
currentTaskEndDateCopy.setDate(currentTaskEndDateCopy.getDate() + 5);

console.log('New Date object:', currentTaskEndDateCopy);
console.log('taskObject (unchanged!):', taskObject);

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Solution 3:

When you copy an object this way, JavaScript passes a reference to the original value.

If you want to copy the value without the reference, you need to do a deep clone. check out _.cloneDeep from lodash