Understanding unique keys for array children in React.js

Question

I\'m building a React component that accepts a JSON data source and creates a sortable table.
Each of the dynamic data rows has a unique key assigned to it but I\'m stil

Answer 1

Warning: Each child in an array or iterator should have a unique "key" prop.

This is a warning as for array items which we are going to iterate over will need a unique resemblance.

React handles iterating component rendering as arrays.

Better way to resolve this is provide index on the array items you are going to iterate over.for example:

class UsersState extends Component
    {
        state = {
            users: [
                {name:"shashank", age:20},
                {name:"vardan", age:30},
                {name:"somya", age:40}
            ]
        }
    render()
        {
            return(
                    

                        {
                            this.state.users.map((user, index)=>{
                                return {user.name}
                            })
                        }
                    
                )
        }

index is React built-in props.