What's the usage of "key" property inside navlink component in react router-CodePudding

There seems no API includes the key property in the NavLink component, react-router. The usage would be like below (in a JSX map loop).

<NavLink key={index} to={`${url}/staff/${staff.id}`}>{staff.name}</NavLink>

My question is: what's the intention of designing such a property? Is there any other use case? Thank you.

CodePudding user response：

In React, when you create a list of elements, you need to identify these elements uniquely. So you use keys.

Using keys allows React to identify which items in the list are changed or updated.

CodePudding user response：

It's for when you are trying to map an array, but not related to the NavLink.