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I have an Object a like that:
const a = { user: { … groups: […] … } } whereby there are a lot more properties in a.user
And I would like to change only the a.user.groups value. If I do this:
const b = Object.assign({}, a, { user: { groups: {} } }); b doesn't have any other Property except b.user.groups, all others are deleted. Is there any ES6 way to only change the nested property, without loosing all the other, with Object.assign?
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Description. Properties in the target object are overwritten by properties in the sources if they have the same key. Later sources' properties overwrite earlier ones. The Object.assign() method only copies enumerable and own properties from a source object to a target object.
To update nested properties in a state object in React: Pass a function to setState to get access to the current state object. Use the spread syntax (...) to create a shallow copy of the object and the nested properties. Override the properties you need to update.
Object. assign does not copy prototype properties and methods. This method does not create a deep copy of Source Object, it makes a shallow copy of the data. For the properties containing reference or complex data, the reference is copied to the destination object, instead of creating a separate object.
After some trying I could find a solution that looks pretty nice like that:
const b = Object.assign({}, a, { user: { ...a.user, groups: 'some changed value' } }); To make that answer more complete here a tiny note:
const b = Object.assign({}, a) is essentially the same as:
const b = { ...a } since it just copies all the properties of a (...a) to a new Object. So the above can written as:
const b = { ...a, //copy everything from a user: { //override the user property ...a.user, //same sane: copy the everything from a.user groups: 'some changes value' //override a.user.group } } If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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