ReactJS TypeScript pure component with children

Tomáš Hübelbauer picture Tomáš Hübelbauer · Jun 14, 2016 · Viewed 7.3k times · Source

I have a TSX component that is a container wrapping its children like this:

import * as React from "react";

interface IProps extends React.Props<Box> {
}

interface IState {
}

export class Box extends React.Component<IProps, IState> {
    render() {
        return (
            <div>
                <h3>Check this out:</h3>
                {this.props.children}
            </div>);
    }
}

I also have some pure components, like this one:

// ReSharper disable once InconsistentNaming - React components must start with a capital letter.
export function LabelTest(props: { label: string }) {
    return (
        <div style={{ display: "flex" }}>
            <label style={{ flex: "1 0 0" }}>{props.label}</label>
            <div style={{ width: "auto" }}>
                This is a pure component.
            </div>
        </div>);
}

I can't for the life of me figure out how to make a pure container component though. The declaration looks alright and shows no errors:

// ReSharper disable once InconsistentNaming - React components must start with a capital letter.
export function LabelBox(props: { label: string, children: React.ReactNode }) {
  return (
    <div style={{ display: "flex" }}>
      <label style={{ flex: "1 0 0" }}>{props.label}</label>
      <div style={{ width: "auto" }}>
        {props.children}
      </div>
    </div>);
}

children is React.ReactNode because that's what it is in React.Props<X>.

When used I get TS2324 Property 'children' is missing in type 'IntrinsicAttributes & { label: string; children: ReactElement | string | number | {} | (Reac....

// ReSharper disable once InconsistentNaming - React components must start with a capital letter.
export function LabelNumberInput(props: { label: string, value: number }) {
  return (
    <LabelBox label={props.label}>
      <input type="number" value={props.value} />
    </LabelBox>);
}

I can't say something like the snippet down below because it will say Cannot find symbol 'LabelBox' in external module _.tsx (it's the file in which all of this code is). Doesn't matter if I put the function or the interface first, but it feels wrong overall anyway.

interface ILabelBoxProps extends React.Props<LabelBox> { label: string }
export function LabelBox(props: ILabelBoxProps) {
  return (
    <div style={{ display: "flex" }}>
      <label style={{ flex: "1 0 0" }}>{props.label}</label>
      <div style={{ width: "auto" }}>
        {props.children}
      </div>
    </div>);
}

What's the right way to make a pure TypeScript React component capable of taking children just like a full class component would? Is this possible? I don't think it should not be, it's still a stateless component and children are just a special kind of props, really the real problem seems to be the tooling here (Visual Studio) which doesn't map the TSX content node to the children prop.

Answer

basarat picture basarat · Jun 15, 2016

What's the right way to make a pure TypeScript React component capable of taking children just like a full class component would

Sample 🌹:

interface PrimitiveProps extends React.HTMLProps<HTMLDivElement>{
   myAdditionalProp:any;
};

export const Content = (allProps: PrimitiveProps) => {
    const {myAdditionalProp, ...props} = allProps;
    return (
        <div data-comment="Content" {...props}/>;
    );
};

Of course you are free to do whatever with myAdditionalProp and put in more props into PrimitiveProps if you want to. Just be sure to remove them from allProps before passing it throught. Note that children get passed as its a part of allProps and thus props.