javascript - 如何使用 JavaScript 创建具有多个可选参数的搜索?
问题描述
我目前拥有的“作品”,但是每个参数都取决于最后一个。我的目标是允许用户使用任意数量的搜索字段来过滤帖子,但我似乎无法理解如何实际执行它。
搜索字段的代码:
import React from "react";
import { Input, DropDown } from "../Form";
import "./index.css";
function Sidebar(props) {
return (
<div className="sidebar-container">
<p>Search Posts: {props.carMake}</p>
<div className="field-wrap">
<Input
value={props.carMake}
onChange={props.handleInputChange}
name="carMake"
type="text"
placeholder="Manufacturer"
/>
</div>
<div className="field-wrap">
<Input
value={props.carModel}
onChange={props.handleInputChange}
disabled={!props.carMake}
name="carModel"
type="text"
placeholder="Model"
/>
</div>
<div className="field-wrap">
<Input
disabled={!props.carModel || !props.carMake}
value={props.carYear}
onChange={props.handleInputChange}
name="carYear"
type="text"
placeholder="Year"
/>
</div>
<div className="field-wrap">
<DropDown
//disabled={!props.carModel || !props.carMake || !props.carYear}
value={props.category}
onChange={props.handleInputChange}
name="category"
type="text"
id="category"
>
<option>Select a category...</option>
<option>Brakes</option>
<option>Drivetrain</option>
<option>Engine</option>
<option>Exhaust</option>
<option>Exterior</option>
<option>Intake</option>
<option>Interior</option>
<option>Lights</option>
<option>Suspension</option>
<option>Wheels & Tires</option>
</DropDown>
</div>
</div>
);
}
export default Sidebar;
这是父组件的代码(实际过滤数据的地方):
import React, { Component } from 'react';
import Sidebar from '../../components/Sidebar';
import API from '../../utils/API';
import PostContainer from '../../components/PostContainer';
import { withRouter } from 'react-router';
import axios from 'axios';
import './index.css';
class Posts extends Component {
constructor(props) {
super(props);
this.state = {
posts: [],
carMake: '',
carModel: '',
carYear: '',
category: 'Select A Category...'
};
this.signal = axios.CancelToken.source();
}
componentDidMount() {
API.getAllPosts({
cancelToken: this.signal.token
})
.then(resp => {
this.setState({
posts: resp.data
});
})
.catch(function(error) {
if (axios.isCancel(error)) {
console.log('Error: ', error.message);
} else {
console.log(error);
}
});
}
componentWillUnmount() {
this.signal.cancel('Api is being canceled');
}
handleInputChange = event => {
const { name, value } = event.target;
this.setState({
[name]: value
});
};
handleFormSubmit = event => {
event.preventDefault();
console.log('Form Submitted');
};
render() {
const { carMake, carModel, carYear, category, posts } = this.state;
const filterMake = posts.filter(
post => post.carMake.toLowerCase().indexOf(carMake.toLowerCase()) !== -1
);
const filterModel = posts.filter(
post => post.carModel.toLowerCase().indexOf(carModel.toLowerCase()) !== -1
);
const filterYear = posts.filter(
post => post.carYear.toString().indexOf(carYear.toString()) !== -1
);
const filterCategory = posts.filter(
post => post.category.toLowerCase().indexOf(category.toLowerCase()) !== -1
);
return (
<div className='container-fluid'>
<div className='row'>
<div className='col-xl-2 col-lg-3 col-md-4 col-sm-12'>
<Sidebar
carMake={carMake}
carModel={carModel}
carYear={carYear}
category={category}
handleInputChange={this.handleInputChange}
handleFormSubmit={event => {
event.preventDefault();
this.handleFormSubmit(event);
}}
/>
</div>
<div className='col-xl-8 col-lg-7 col-md-6 col-sm-12 offset-md-1'>
{carMake && carModel && carYear && category
? filterCategory.map(post => (
<PostContainer post={post} key={post.id} />
))
: carMake && carModel && carYear
? filterYear.map(post => (
<PostContainer post={post} key={post.id} />
))
: carMake && carModel
? filterModel.map(post => (
<PostContainer post={post} key={post.id} />
))
: carMake
? filterMake.map(post => (
<PostContainer post={post} key={post.id} />
))
: posts.map(post => <PostContainer post={post} key={post.id} />)}
</div>
</div>
</div>
);
}
}
export default withRouter(Posts);
API 返回的数据是对象数组的形式,如下所示:
[{
"id":4,
"title":"1995 Toyota Supra",
"desc":"asdf",
"itemImg":"https://i.imgur.com/zsd7N8M.jpg",
"price":32546,
"carYear":1995,
"carMake":"Toyota",
"carModel":"Supra",
"location":"Phoenix, AZ",
"category":"Exhaust",
"createdAt":"2019-07-09T00:00:46.000Z",
"updatedAt":"2019-07-09T00:00:46.000Z",
"UserId":1
},{
"id":3,
"title":"Trash",
"desc":"sdfasdf",
"itemImg":"https://i.imgur.com/rcyWOQG.jpg",
"price":2345,
"carYear":2009,
"carMake":"Yes",
"carModel":"Ayylmao",
"location":"asdf",
"category":"Drivetrain",
"createdAt":"2019-07-08T23:33:04.000Z",
"updatedAt":"2019-07-08T23:33:04.000Z",
"UserId":1
}]
如上所示,我试图只注释掉下拉列表的“禁用”属性,但这会导致它完全停止作为过滤器工作,并返回所有结果,无论选择如何。这是由于我检查每个过滤器的三元运算符混乱造成的。有没有更好的方法可以做到这一点?
解决方案
即使@Nina Lisitsinskaya 的回答是正确的,我也不会有一个庞大的if
s 列表,并且只完成了过滤器连接。
这样添加另一种过滤方式更容易且可读性强。解决方案虽然是相似的。
render() {
const { carMake = '', carModel = '', carYear = '', category = '', posts } = this.state;
let filtered = [...posts];
filtered = filtered
.filter(post => post.carMake.toLowerCase().indexOf(carMake.toLowerCase()) !== -1)
.filter(post => post.carModel.toLowerCase().indexOf(carModel.toLowerCase()) !== -1)
.filter(post => post.carYear.toString().indexOf(carYear.toString()) !== -1)
.filter(post => post.category.toLowerCase().indexOf(category.toLowerCase()) !== -1)
...
}
当然后来你想filtered
在 JSX 表达式中使用类似的 this,否则没有什么可显示的。
...
<div className='col-xl-8 col-lg-7 col-md-6 col-sm-12 offset-md-1'>
{filtered.map(post => <PostContainer post={post} key={post.id} />)}
</div>
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