React Typescript how send props and use it in child component

Question

I'm using React and TypeScript and trying to pass some data like prop to child component and use it in child component. But i'm getting error and i can't understand why is happened and how fix it. I'm beginner on TypeScript also.

Here is my parent component

import * as React from "react";
import ChildComponent from "./ChildComponent";

const data = [
  {
    title: "A",
    id: 1,
  },
  {
    title: "B",
    id: 1,
  },
];

const ParentComponent = () => {
   return (
      <ChildComponent items={data} />
   )
}

export default ParentComponent;

Here is error in parent component at items

(JSX attribute) items: {
    title: string;
    id: number;
}[]
Type '{ items: { title: string; id: number; }[]; }' is not assignable to type 'IntrinsicAttributes'.
  Property 'items' does not exist on type 'IntrinsicAttributes'.ts(2322)

And when in regular react and es6 i can use this props in child component like this:

const ChildComponent = (props) => {
   return (
      <div>
         {props.items.map((item) => (
           <p to={item.title}></p>
         ))} 
      </div>
   )
}

but have use this props in child component if it will be TypeScript?

Answer 1

You need to specify what type of props the child component wants. For example:

interface Item {
  title: string;
  id: number;
}

interface ChildComponentProps {
  items: Item[]
}

const ChildComponent: React.FC<ChildComponentProps> = (props) => {
  return (
    <div>
      {props.items.map((item) => (
        <p to={item.title}></p>
      ))} 
    </div>
  )
}

Answer 2

Added to the reply, if the props can be null, you put a question mark.

interface ChildComponentProps {
  items?: Item[]
}