嵌套对象：使用相同的名称更新所有属性

Question

I have a quit complex object with multiple nested objects. This object i want to copy and update all id attributes.

So this:

{
  id: 1,
  name: "A",
  car: {
    id: 2,
    vendor: "xy"
    }
  ..
}

should become this:

{
  id: 6,
  name: "A",
  car: {
    id: 7,
    vendor: "xy"
    }
  ..
}

Is there a way to this in a short and generic way with JavaScript (TypeScript)?

Update: What I did so far:

const a = new MyClass();
a.id = uuid();
a.name = "A"
a.car = new Car();
a.car.id = uuid();
a.car.vendor = "xy"

//copy a
const b = JSON.parse(JSON.stringify(a));

All I want to do is increase all ids in b by 5.

Answer 1

You can loop through all the items in b and do two things. If it's an id property, change it (add 5). If it's an object, loop through and check both the same conditions (recursive function). Here's how you could do it:

function checkObject(obj) {
    Object.keys(obj).forEach(function(prop) { 
        if (typeof obj[prop] == "object" && prop !== null) { 
            checkObject(obj[prop]);
        }
        else if (prop == "id") {
            obj[prop] += 5;
        }
    })
}

Then you'd call it like so:

 function checkObject(obj) { Object.keys(obj).forEach(function(prop) { if (typeof obj[prop] == "object" && prop !== null) { checkObject(obj[prop]); } else if (prop == "id") { obj[prop] += 5; } }) } var b = { id: 1, name: "A", car: { id: 2, vendor: "xy" } } checkObject(b); console.log(b); 

Answer 2

Here is a function that clones the original object into a new one where each id property receives a new value generated by a given uuid function:

 function assignId(data, uuid) { return Object(data) !== data ? data : Object.assign({}, ...Object.entries(data).map( ([k, v]) => ({ [k]: k === "id" ? uuid() : assignId(v, uuid) }) )); } // Example use: function uuid() { return uuid.next = (uuid.next || 1000) + 1; } const a = { id: 1, name: "A", car: { id: 2, vendor: "xy" } }; const b = assignId(a, uuid); console.log(b);