reactjs - 如何在 typescript 中正确使用 Formik 的 useField 钩子(Hook)

Question

我关注了 documentation 的所有内容
并观看了 Ben Awad on YouTube 的教程.而且，我仍然无法让它工作。

const TextField = (props: FieldHookConfig<{}>) => {
    const [field] = useField(props);
        return (
            <div>
                <input {...field} {...props}/>
            </div>
        );
    };

我用了FieldHookConfig作为 Prop 的类型，因为 useField期待 string或 FieldHookConfig基于 Field.d.ts 文件。然而 typescript 仍然不开心。

它在这一行提示<input {...field} {...props}/>

(property) JSX.IntrinsicElements.input: React.DetailedHTMLProps<React.InputHTMLAttributes<HTMLInputElement>, HTMLInputElement>
Type '{ ref?: string | ((instance: HTMLInputElement | null) => void) | RefObject<HTMLInputElement> | null | undefined; key?: string | number | undefined; ... 289 more ...; innerRef?: ((instance: any) => void) | undefined; } | { ...; } | { ...; }' is not assignable to type 'DetailedHTMLProps<InputHTMLAttributes<HTMLInputElement>, HTMLInputElement>'.
  Type '{ ref?: string | ((instance: HTMLSelectElement | null) => void) | RefObject<HTMLSelectElement> | null | undefined; key?: string | number | undefined; ... 269 more ...; checked?: boolean | undefined; }' is not assignable to type 'DetailedHTMLProps<InputHTMLAttributes<HTMLInputElement>, HTMLInputElement>'.
    Type '{ ref?: string | ((instance: HTMLSelectElement | null) => void) | RefObject<HTMLSelectElement> | null | undefined; key?: string | number | undefined; ... 269 more ...; checked?: boolean | undefined; }' is not assignable to type 'ClassAttributes<HTMLInputElement>'.
      Types of property 'ref' are incompatible.
        Type 'string | ((instance: HTMLSelectElement | null) => void) | RefObject<HTMLSelectElement> | null | undefined' is not assignable to type 'string | ((instance: HTMLInputElement | null) => void) | RefObject<HTMLInputElement> | null | undefined'.
          Type '(instance: HTMLSelectElement | null) => void' is not assignable to type 'string | ((instance: HTMLInputElement | null) => void) | RefObject<HTMLInputElement> | null | undefined'.
            Type '(instance: HTMLSelectElement | null) => void' is not assignable to type '(instance: HTMLInputElement | null) => void'.
              Types of parameters 'instance' and 'instance' are incompatible.
                Type 'HTMLInputElement | null' is not assignable to type 'HTMLSelectElement | null'.
                  Type 'HTMLInputElement' is missing the following properties from type 'HTMLSelectElement': length, options, selectedIndex, selectedOptions, and 4 more.ts(2322)

Answer 1

有两个问题，第一，不能传播props <input> 上的变量元素，由于不兼容的类型(如错误中指定)。其次，FieldHookConfig 的泛型类型不应该是 {} , 而应该是 string所以要修复它，假设您使用的是 <TextField>像这样的元素

<TextField
  name="firstName"
  type="text"
  placeholder="Jane"
/>

然后在你的TextField里面定义，你会写

const TextField = (props: FieldHookConfig<string>) => {
  const [field] = useField(props);
  return (
    <div>
      {/* no need to pass the name field because Formik will accept
      that prop internally and pass it to the field variable */}
      <input {...field} placeholder={props.placeholder} type={props.type} />
    </div>
    );
};