update nested object inside object in typescript

Question

I am looking for the best solution to update the key values inside the nested objects in angular.

The solution which I know is manually running 2 for loops and updating each property.

below is what I have tried and what I want to achieve.

Are there any options to avoid ending up running 2 loops?

I was thinking to use map option inside the loop but not getting what I expected.

obj1 = [
   {
      "val":"type1",
      "removed":"N",
      "data":[
         {
            "label":"type1-a",
            "removed":"N",
            "dataid":16
         },
         {
            "label":"type1-b",
            "removed":"N",
            "dataid":26
         }
      ]
   },
   {
      "val":"type2",
      "removed":"N",
      "data":[
         {
            "label":"type2-a",
            "removed":"N",
            "dataid":12
         },
         {
            "label":"type2-b",
            "removed":"N",
            "dataid":34
         }
      ]
   }
]


Result = 

obj1 = [
   {
      "val":"type1",
      "removed":"N",
      "data":[
         {
            "newlabel":"type1-a",
            "removed":"N",
            "newid":16,
            "extraparam1":null
         },
         {
            "newlabel":"type1-b",
            "removed":"N",
            "newid":26,
            "extraparam1":null
         }
      ]
   },
   {
      "val":"type2",
      "removed":"N",
      "data":[
         {
            "newlabel":"type2-a",
            "removed":"N",
            "newid":12,
             "extraparam1":null
         },
         {
            "newlabel":"type2-b",
            "removed":"N",
            "newid":34,
            "extraparam1":null
         }
      ]
   }
]

obj1.forEach(val=>{

if(val.data){
 //logic to modify the existing object
}

});

Sebastian Puchet · Accepted Answer · 2020-07-03 14:02:28Z

3

If you want to keep the main object without changes. You can do something like this:

const obj1 = [
    {
        "val":"type1",
        "removed":"N",
        "data":[
            {
                "label":"type1-a",
                "removed":"N",
                "dataid":16
            },
            {
                "label":"type1-b",
                "removed":"N",
                "dataid":26
            }
        ]
    },
    {
        "val":"type2",
        "removed":"N",
        "data":[
            {
                "label":"type2-a",
                "removed":"N",
                "dataid":12
            },
            {
                "label":"type2-b",
                "removed":"N",
            "dataid":34
            }
        ]
    }]
;

let result = obj1.map(({ data, ...values }) => {
    return {
        ...values,
        data: data.map(({ label, dataid, ...rest }) => ({
            ...rest,
            newlabel: label,
            newid: dataid,
            extraparam1: null
        }))
    }
})

This approach will return a new clean copy of the object.

But if you want to update the object. You can do something like this:

obj1.forEach(val => {
    if (val.data) {
        val.data = val.data.map(({ label, dataid, ...rest }) => ({
            ...rest,
            newlabel: label,
            newid: dataid,
            extraparam1: null
        }))
    }
});

edited Jul 3, 2020 at 14:02

answered Jul 3, 2020 at 1:46

Sebastian Puchet

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6 Comments

Bravo Over a year ago

If I have 10 extra property do I need to write each of them ? Is there any other approach to avoid writing all property again?

Sebastian Puchet Over a year ago

Where those extra properties will come from? Will be the same for each data.element?

Bravo Over a year ago

no that is the outside object property such as val and removed.

Sebastian Puchet Over a year ago

take a look at my edit. Now you can see a ({ label, dataid, ...rest }), that just deconstruct label and dataid because you want to change the object key, and ...rest means all those other properties you don't want to change.

Bravo Over a year ago

Thanks a lot... I was about to use this on one of the function

|

Dewanshu · Accepted Answer · 2020-07-03 02:06:22Z

1

Try This

obj1.map(data => ({label:data.label, dataid:data.dataid, removed:data.removed, param: null} ))

answered Jul 3, 2020 at 2:06

Dewanshu

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1 Comment

Bravo Over a year ago

how it iterates through all objects?

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