搜索对象后反应组件的更新状态

时间:2020-03-21 22:09:48

标签: javascript reactjs search sanity use-state

我有一个从reactIcons npm软件包https://www.npmjs.com/package/react-icons输出的对象,我正在使用import * as ReactIcons from 'react-icons/fa'从其中一个文件夹导入所有内容,我正在使用sanity studio,创建了一个文本输入,其值搜索并运行搜索功能,该功能对我从reactIcons fa文件夹中抓取的对象的值运行包含,并记录匹配的值。现在,我想获取这些值并使用useState()更新一个react组件。但是,我收到以下错误Uncaught ReferenceError: setIcon is not defined,并且SetIcon是useState数组中的setter函数。到目前为止,这是我的代码

import React, { useState } from 'react';
import PropTypes from 'prop-types'
import FormField from 'part:@sanity/components/formfields/default'
import PatchEvent, {set, unset} from 'part:@sanity/form-builder/patch-event'
import * as ReactIcons from 'react-icons/fa'


console.log(ReactIcons);

const createPatchFrom = value => PatchEvent.from(value === '' ? unset() : set(String(value)))

const Example = value => {
  const [icon, setIcon] = useState();

  return (
   <div>{icon}</div>
  );
}

const search = value => {
  console.log(value);
    Object.keys(ReactIcons).map(go => {
    if (go.toLowerCase().includes(value) === true){
      console.log(go);
      setIcon(go);
    }
  })
}



class IconPickerCustom extends React.Component{

    static propTypes = {
        value: PropTypes.string,
        onChange: PropTypes.func.isRequired
    };

    render = () =>{
        const {type, value, onChange} = this.props
        return (
          <>
            <FormField label={type.title} description={type.description}>
              <input
                type="text"
                value={value === undefined ? '' : value}
                onChange={event => onChange(createPatchFrom(event.target.value))}
                ref={element => this._inputElement = element}
              />
            </FormField>
            <input
              type="text"
              onChange={event => search(event.target.value)}
            />
            {Object.values(ReactIcons).map(X =>{
              return (
                <>
              <X/>
              </>
              );
            })}
            {console.log(ReactIcons.Fa500Px)}
            <ReactIcons.Fa500Px/>
            <Example/>
          </>
        )
    }
}

export default IconPickerCustom;

1 个答案:

答案 0 :(得分:2)

React具有两种类型的组件,类组件和功能组件(以前称为无状态组件)。当您意识到需要在功能组件内部进行状态并且不希望将其转换为类组件时,可以在功能组件中使用挂钩。

useState()挂钩允许我们在功能组件中添加状态。

类组件

//initialize state
constructor(props) {
    super(props);
    this.state = {foo: bar};
}

//set state
this.setState({foo: baz});

//read state
this.state.foo;

功能组件
(带有useState()挂钩)

//initialize state
const [icon, setIcon] = useState("myInitialValue");

//set state
setIcon("myNewValue");

//read state
{icon}

话虽这么说,您已经有了一个类组件,所以这里不需要使用钩子。

class IconPickerCustom extends React.Component{

constructor(props) {
    super(props);
    this.state = { icon: "nothing" };
}

static propTypes = {
    value: PropTypes.string,
    onChange: PropTypes.func.isRequired
};

const createPatchFrom = value => PatchEvent.from(value === '' ? unset() : set(String(value)));

const search = value => {
    Object.keys(ReactIcons).map(go => 
        ({ go.toLowerCase().includes(value) ? 
           this.setState({icon:go}) : null;}) 
}

render = () =>{
    const {type, value, onChange} = this.props
    return (
      <>
        <FormField label={type.title} description={type.description}>
          <input
            type="text"
            value={value === undefined ? '' : value}
            onChange={event => onChange(createPatchFrom(event.target.value))}
            ref={element => this._inputElement = element}
          />
        </FormField>
        <input
          type="text"
          onChange={event => search(event.target.value)}
        />
        {Object.values(ReactIcons).map(X =>{
          return (
            <>
          <X/>
          </>
          );
        })}
        {console.log(ReactIcons.Fa500Px)}
        <ReactIcons.Fa500Px/>
        <Example/>
      </>
    )
}
}

export default IconPickerCustom;

您将要遵循这些原则。如果您有任何问题,请告诉我。