Using typescript enum and react to expect string prop

Question

I'm trying to strict type a Button component in React.

How can I expect a prop with a specific string value?

My current attempt results in Type '"primary"' is not assignable to type 'ButtonLevel'

enum ButtonLevel {
  Primary = "primary",
  Secondary = "secondary",
  Warning = "warning"
}

interface IButtonProps {
  level: ButtonLevel,
  disabled?: boolean
}

function MyButton(props: IButtonProps) {
  return (<Button>ABC</Button>)
}

function test() {
  return (<MyButton level="primary" ></MyButton>)
}

Answer 1

Right... just enter the values pipe separated

interface IButtonProps {
  level: "primary" | "secondary" | "warning",
  disabled?: boolean
}

function test() {
  return (<MyButton level="ad" disabled >Continue</MyButton>)
}

Which then warns a component consumer the value is invalid.

Answer 2

当您使用枚举时，您传递的是 ButtonLevel.Primary 而不是“primary”，枚举的重点是强类型并防止输入错误。