How can I edit a specific value from a json array in Javascript

I fully agree with Dinesh Patil's solution. however, writing in arrow function makes the map() method a lot more easier to understand.

   const jsonObj = [
    {name: 'abc', balance: 400},
    {name: 'jkl', balance: 400},
    {name: 'erp', balance: 400}
   ]

   pos = jsonObj.map(val => val.name).indexOf('jkl')

   jsonObj[pos].balance = 200

Don't use forEach... Use Arra.find https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find which skip the rest when something found...

yourArrry.find((el)=>el.name == nameToFind).balance = newBalance;

You can store return value of find in a variable and assign new value after verifying when it is not undefined

Suggest the idea like this.

• you have to know the 'name' (ie. 'Jxsh') you want to update the balance.
• then find out an index of that name in the users array (ie. index = 2).
• use that index (ie. users[2]) to update the balance to amount you want (ie. users[2].balabce=900 ).

In my case I would do something like this:

let ids = {};    
let arr = [
    {
        "name": "Rubs",
        "uuid": "9e24f3f5-7089-4f3c-bf63-211c24a0744e",
        "balance": 500
    },
    {
        "name": "Foxitic",
        "uuid": "39f6521c-5a18-48e4-8c84-6f1bb6c8de90",
        "balance": 500
    },
    {
        "name": "Jxsh",
        "uuid": "5f06ea31-3a20-43fc-8ce8-60ac7e7b0971",
        "balance": 500
    },
    {
        "name": "Bopeebo",
        "uuid": "91a5d15b-cca0-44e9-a513-91fe7ab05715",
        "balance": 500
    }
  ]
    arr.map((item, index) => {ids[item.uuid] = index});

    ////update balance code
    arr[ids["91a5d15b-cca0-44e9-a513-91fe7ab05715"]].balance = 333;

This link makes be useful for you. https://stackoverflow.com/a/16008853/10802524

Following ways can help you to achieve what you want. First

• You can iterate a loop for each object.
• Add if condition to match the specific name.
• Finally, modify the balance of that index of the matched name.

const jsonObj = [{ name : "xyz", balance: 500},{ name : "abc", balance: 800},{ name : "efg", balance: 50}];

for(let obj of jsonObj){
If(obj.name === "abc")
     obj.balance = 700; // changing value for balance
}

Second

• You can use the map to get the index of a specific name.
• Modify the balance's value of that index.

const jsonObj = [{ name : "xyz", balance: 500},{ name : "abc", balance: 800},{ name : "efg", balance: 50}];

pos = jsonObj.map((obj)=> return obj.name;).indexOf('abc')

jsonObj[pos].balance = 700;

Hope this will help you