如何将对象中数组的索引值添加到键

Question

I have an object in variable info as :

0: {ProId: "Space", Name: "cake", Quantity: 1}
1: {ProId: "new", Name: "walk", Quantity: 1}

I am trying to change the Quantity value to it's index+1 for each index ,

I have tried to have a static value as:

  for (var key in obj){
    var value= obj[key];
    value['Quantity'] = 5;
  }

Expected O/p:

console.log(info)
    0: {ProId: "Space", Name: "cake", Quantity: 1}
    1: {ProId: "new", Name: "walk", Quantity: 2}
    2: {............................Quantity: 3}.....

But May I know how can I have the Quantity value as above mentioned

Answer 1

Some hints:

• Take an array instad of an object, if you need an easy iterable data structure. This gives a control over the iteration order, too.
• Use numbers for number values. If you need later a (formatted) string apply toString to it.

For getting a new value of a property, you could mutate the given data

Using:

• Array#forEach for vititing all items of the array,
• an arrow function , a short form of a function.

 var array = [{ ProId: "Space", Name: "cake", Quantity: "1" }, { ProId: "new", Name: "walk", Quantity: "1" }]; array.forEach((object, i) => object.Quantity = i + 1); console.log(array);

Or get new objects by mapping the array.

Using:

• Array#map for getting a new array,
• spread syntax ... for taking all properties of an object into a new object

 var array = [{ ProId: "Space", Name: "cake", Quantity: "1" }, { ProId: "new", Name: "walk", Quantity: "1" }], newArray = array.map((object, i) => ({ ...object, Quantity: i + 1 })); console.log(newArray);

Answer 2

Use forEach with index and add Quantity at certain index + index . And use toString() method as you want to have values in String format.

 var obj = [{ProId: "Space", Name: "cake", Quantity: "1"}, {ProId: "new", Name: "walk", Quantity: "1"}] obj.forEach(function(el,idx){ el.Quantity=(idx+parseInt(el.Quantity)).toString() }) console.log(obj);

Answer 3

You can map the array and return a new array but merging the old object with new object with updated Quantity value like:

 const data = [{ProId: "Space", Name: "cake", Quantity: "1"}, {ProId: "new", Name: "walk", Quantity: "1"}], updatedData = data.map((x, i)=> ({...x, Quantity: ++i})); console.log(updatedData)

 .as-console-wrapper { max-height: 100% !important; top: 0; }

A simple example of updating an object key value (which is done here inside the map() method) is like:

 let obj = { a: 0, b: 0}; let newObj = { ...obj, a: 1 }; console.log( newObj )

Answer 4

Try using:

let obj = {
 '0': {ProId: "Space", Name: "cake", Quantity: "1"},
 '1': {ProId: "new", Name: "walk", Quantity: "1"}
}
for(key in obj) {
   let qty = String(Number(obj[key]['Quantity'])+Number(key))
   obj[key]['Quantity'] = qrt;
}

Answer 5

One way is to map your current array.

const info2 = info.map((product, index) => ({ ...product, Quantity: index + 1 }));

In case you want Quantity as a string do this Quantity: index + 1 + '' , or Quantity: (index + 1).toString() . Whatever suits you.

Answer 6

You can also try this:

 let info = { 0: { ProId: "Space", Name: "cake", Quantity: "1" }, 1: { ProId: "new", Name: "walk", Quantity: "1" } } let index = 1; Object.values(info).map(function(val) { val.Quantity = index; index++; }); console.log(info);

Answer 7

I made it in the case you are using just the object, without set up as an array.

let info = {
    0: { ProId: "Space", Name: "cake", Quantity: "1" },
    1: { ProId: "new", Name: "walk", Quantity: "2" },
    2: { ProId: "foo", Name: "bar", Quantity: "3" }
}

function incrementQuantify(obj) {
    let _newInfo = {};

    for (const key of Object.keys(obj)) {
        info[key].Quantity = parseInt(info[key].Quantity, 10) + 1;
        _newInfo[key] = info[key];
    }

    return _newInfo;
}
/*
{
  '0': { ProId: 'Space', Name: 'cake', Quantity: 2 },
  '1': { ProId: 'new', Name: 'walk', Quantity: 3 },
  '2': { ProId: 'foo', Name: 'bar', Quantity: 4 }
}
*/
console.log(incrementQuantify(info));

Shorter way:

let info = { 0: { ProId: "Space", Name: "cake", Quantity: "1" }, 1: { ProId: "new", Name: "walk", Quantity: "2" }, 2: { ProId: "foo", Name: "bar", Quantity: "3" } }
for (const key of Object.keys(info)) info[key].Quantity = parseInt(info[key].Quantity, 10) + 1;
console.log(info);

edit: I already made an way to work with arrays too!

let info = [
    { ProId: "Space", Name: "cake", Quantity: "1" },
    { ProId: "new", Name: "walk", Quantity: "2" },
    { ProId: "foo", Name: "bar", Quantity: "3" }
]

function incrementQuantify(obj) {
    let newObj = obj;
    newObj.Quantity = parseInt(obj.Quantity, 10) + 1;
    return newObj;
}
info.map(incrementQuantify);
/*
[
  { ProId: 'Space', Name: 'cake', Quantity: 2 },
  { ProId: 'new', Name: 'walk', Quantity: 3 },
  { ProId: 'foo', Name: 'bar', Quantity: 4 }
]
*/
console.log(info);

Shorter way:

let info = [ { ProId: "Space", Name: "cake", Quantity: "1" }, { ProId: "new", Name: "walk", Quantity: "2" }, { ProId: "foo", Name: "bar", Quantity: "3" } ]; info.map(o => o.Quantity = parseInt(o.Quantity, 10) + 1);
console.log(info);

Hope it helps!