How to update value in array of object in useState hooks-CodePudding

I am new to React Hooks. I have an state which looks like this.

const [myData, setmyData] = useState([
    {
        "OrderId": "ord-898s1",
        "Shoulder Size": "12",
        "Amount": 200,
        "Shoulder Width": "2",
       
    },
{
        "OrderId": "ord-898s2",
        "Shoulder Size": "14",
        "Amount": 790,
        "Shoulder Width": "2",
       
    }
])
var orderID = "ord-898s2"
var AmountToAdd = 100

I want to update the Amount Value in orderID ord-898s2. By adding 100, the Amount Value in orderID ord-898s2 should be 890

console.log(myData)

Required Output:

[
    {
        "OrderId": "ord-898s1",
        "Shoulder Size": "12",
        "Amount": 200,
        "Shoulder Width": "2",

    },
{
        "OrderId": "ord-898s2",
        "Shoulder Size": "14",
        "Amount": 890,
        "Shoulder Width": "2",

    }
]

I tried these.

 const result2 = myData.map((item) => {
        if (item.OrderId === orderID) {
        
            return { ...item, ["Amount"]:item.Amount  100  }
         

        }
        
        return item
      })
     setmyData(result2)

it failed. I don't know how to make it. Please help me with some solutions.

CodePudding user response：

You could do it like this:

    setmyData((prev) =>
      prev.map((el) =>
        el.OrderId === "ord-898s2" ? { ...el, Amount: el.Amount   100 } : el
      )
    );

CodePudding user response：

Try below code.

var data = [
    {
        "OrderId": "ord-898s1",
        "Shoulder Size": "12",
        "Amount": 200,
        "Shoulder Width": "2",
       
    },
{
        "OrderId": "ord-898s2",
        "Shoulder Size": "14",
        "Amount": 790,
        "Shoulder Width": "2",
       
    }
];

var orderID = "ord-898s2"
var AmountToAdd = 100

data.forEach((item) =>
  item.OrderId === orderID ? item.Amount = item.Amount   AmountToAdd : item.Amount);
  
 console.log(data);