Question

import React, { Component} from 'react';  
import Select from 'react-select';  
import 'react-select/dist/react-select.css';

const partsType = [
    {value: 'front_parts', label: 'Part Condition-Front'},
    {value: 'left_parts', label: 'Part Condition-Left'},
    {value: 'back_parts', label: 'Part Condition-Back'},
    {value: 'right_parts', label: 'Part Condition-Right'},
    {value: 'top_bottom_parts', label: 'Part Condition-Top/Bottom'},
    {value: 'glass', label: 'Glass Condition'},
    {value: 'electrical_parts', label: 'Electrical Parts'},
    {value: 'non_electrical_parts', label: 'Non-Electrical Parts'}
];

const getParts = () => {
    return fetch(
      "http://localhost:4000/left_parts",
      {
          method: 'get'
      }
    )
      .then(response => {
          if(response.status >= 400) {
              throw new Error("error");
          }
          return response.json()
      })
      .then(parts => {
          let partsName = [];
          for(let part of parts) {
              partsName.push({value: part.promptCode, label: part.text})
          }
          return {options: partsName};
      })
      .catch(err => {
          console.log('could not fetch parts');
          console.log(err);
          return {options: []}
      })
};

class Assess extends Component {

    constructor(props) {
        super(props);
        this.state = {
            partsType:'front_parts'        
    };

    this.handlePartsType = this.handlePartsType.bind(this);

    handlePartsType = (item) => {
        this.setState({
            partsType: item.value
        });
    };

    render() {
        return (
            <div>
                <Select
                    clearable={false}
                    searchable={false}
                    value={this.state.partsType}
                    options={partsType}
                    onChange={this.handlePartsType}
                />

                <Select.Async
                    clearable={false}
                    searchable={false}
                    name="PartNamePolygon"
                    value={this.state.PartNamePolygon}
                    onChange={this.PartNamePolygonSelect}
                    loadOptions={getParts}
                />
            </div>
        );
    }
}

我提供了片段。我现在正在做的是我已经做了两次下拉并使用第一次下拉数据将被改变。现在因为我没有得到如何根据this.state.partsType调用不同的API，因为根据其状态值，它的值将在“getParts”中传递。怎么实现呢？将其值传递给它，以便调用不同的API

Answer 1

试试这个

import React, { Component} from 'react';  
        import Select from 'react-select';  
        import 'react-select/dist/react-select.css';

        const partsType = [
            {value: 'front_parts', label: 'Part Condition-Front'},
            {value: 'left_parts', label: 'Part Condition-Left'},
            {value: 'back_parts', label: 'Part Condition-Back'},
            {value: 'right_parts', label: 'Part Condition-Right'},
            {value: 'top_bottom_parts', label: 'Part Condition-Top/Bottom'},
            {value: 'glass', label: 'Glass Condition'},
            {value: 'electrical_parts', label: 'Electrical Parts'},
            {value: 'non_electrical_parts', label: 'Non-Electrical Parts'}
        ];

        const getParts = (type) => {
            return fetch(
              `http://localhost:4000/${type}`,
              {
                  method: 'get'
              }
            )
              .then(response => {
                  if(response.status >= 400){
                  throw new Error("error");
                  }
                  return response.json()
              })
              .then(parts => {
                  let partsName = [];


                  for(let part of parts) {
                  partsName.push({value: part.promptCode, label: part.text})
                  }


                  return {options: partsName};
              })
              .catch(err => {
                  console.log('could not fetch parts');
                  console.log(err);
                  return {options: []}
              })

        };

        class Assess extends Component {

            constructor(props){
            super(props);
            this.state = {
                partsType:'front_parts'

            };

        this.handlePartsType = this.handlePartsType.bind(this);

        handlePartsType = (item) => {
              this.setState({
                  partsType: item.value
              }, getParts(item.value));

              };

        render() {

            return (
            <div>
            <Select
            clearable={false}
            searchable={false}
            value={this.state.partsType}
            options={partsType}
            onChange={this.handlePartsType}
            />

        <Select.Async
                                  clearable={false}
                                  searchable={false}
                                  name="PartNamePolygon"
                                  value={this.state.PartNamePolygon}
                                  onChange={this.PartNamePolygonSelect}
                                  loadOptions={getParts}
                                />

        </div>
            );
          }
        }

Answer 2

有几个问题：

this.handlePartsType = this.handlePartsType.bind(this);是多余的。构造函数也没有右括号。 Select.Async不应该用于根据外部值加载选项，它会在输入更改时加载选项。

下面是重写的例子：

＆＃13;

		const partsType = [
		    {value: 'front_parts', label: 'Part Condition-Front'},
		    {value: 'left_parts', label: 'Part Condition-Left'},
		    {value: 'back_parts', label: 'Part Condition-Back'},
		    {value: 'right_parts', label: 'Part Condition-Right'},
		    {value: 'top_bottom_parts', label: 'Part Condition-Top/Bottom'},
		    {value: 'glass', label: 'Glass Condition'},
		    {value: 'electrical_parts', label: 'Electrical Parts'},
		    {value: 'non_electrical_parts', label: 'Non-Electrical Parts'}
		];
    
    // test wrapper for fetch to be removed to talk to backend
    const fetch = () => Promise.resolve({json: () => Promise.resolve([{promptCode: 'test', text: 'Test option'}])})

		const getParts = (partsType) => {
		    return fetch(
			  `http://localhost:4000/${partsType}`,
			  {
			      method: 'get'
			  }
			)
			  .then(response => {
			      if(response.status >= 400){
				  throw new Error("error");
			      }
			      return response.json()
			  })
			  .then(parts => {
			      let partsName = [];


			      for(let part of parts) {
				  partsName.push({value: part.promptCode, label: part.text})
			      }


			      return {options: partsName};
			  })
			  .catch(err => {
			      console.log('could not fetch parts');
			      console.log(err);
			      return {options: []}
			  })

		};

		class Assess extends React.Component {
      state = {
			    partsType:'front_parts'
			};

      handlePartsType = (partsType) => {
        getParts(partsType).then(({options}) =>
          this.setState({partsType, partsOptions: options})
        )
      };
      
      componentDidMount() {
        this.handlePartsType(this.state.partsType);
      }

		render() {
		    return (
		    <div>
			<Select
			clearable={false}
			searchable={false}
			value={this.state.partsType}
			options={partsType}
			onChange={({value}) => this.handlePartsType(value)}
			/>
		<Select
				                  clearable={false}
				                  searchable={false}
				                  name="PartNamePolygon"
				                  value={this.state.partNamePolygon}
				                  onChange={this.partNamePolygonSelect}
                          options={this.state.partsOptions}
				                />

		</div>
		    );
		  }
		}


ReactDOM.render(
  <div>
   <Assess/>
  </div>,
  document.getElementById('root')
)

＆＃13;

<html>
<head>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.js"></script>
<script src="https://unpkg.com/classnames/index.js"></script>
<script src="https://unpkg.com/react-input-autosize@1.0.0/dist/react-input-autosize.js"></script>
<script src="https://unpkg.com/react-select@1.0.0-rc.3/dist/react-select.js"></script>


<link rel="stylesheet" href="https://unpkg.com/react-select@1.0.0-rc.3/dist/react-select.css">
</head>
<body>
<div id='root'></div>
</body>
</html>

＆＃13;

条件API调用并在react-select中发送数据

2 个答案: