How to add data to object-CodePudding

I am trying to adddata from another object into a new object while also adding new data const addCardData = { ...optIn, cardId, cardName} here optIn already has cardId and cardName so they are getting replaced by new values, how to make an addCardData such that cardId and cardName not be replaced but added to the object or as a sub object? or is there any other better way to do this?

CodePudding user response：

If your goal is to keep the values from "optIn", you could add them last.

For example:

addCardData =  { 
  cardId, 
  cardName, 
  ...optIn 
};

If your goal is to add both versions of cardId and both versions of cardName, you have two options:

Change the name of cardId and cardName, since an object can only old one attribute with a given name.

For example:

addCardData =  { 
  newCardId: cardId, 
  newCardName: cardName, 
  ...optIn 
};

Add the optIn object as an attribute

addCardData =  { 
  cardId, 
  cardName, 
  optIn
};

Then you can refer to it by addCardData.optIn.cardId.

CodePudding user response：

Here is a way to combine both objects. If any of the properties already exists in optIn it will be changed into an array in addCardData and the new value will then be pushed onto it:

const optIn={a:123,b:456,cardId:789,cardName:"Harry"},cardId=222,cardName="Sally";

const addCardData = {...optIn};
Object.entries({cardId,cardName}).forEach(([k,v])=>{
 (addCardData[k]=Array.isArray(addCardData[k])?addCardData[k]:[addCardData[k]]).push(v)
});

console.log(addCardData);

CodePudding user response：

so converting optIn to a array first and then doing optIn.push({cardId, cardName}) works perfectly without creating any nested objects