应用多个过滤器反应

Question

我有两个按钮,当点击时应该过滤novelty或offer,我能够使它,以便当点击新奇时它会过滤,但我无法做到这样,如果两者都是点击它将过滤两者novelty和offer

我怎样才能做到这一点,当点击新奇和优惠时,它会被这两者过滤掉？

https://www.webpackbin.com/bins/-KpVGNEN7ZuKAFODxuER

import React from 'react'

export default class extends React.Component {
  constructor() {
    super()

    this.state = {
      products: [
        { id: 1, novelty: true, offer: false, name: 'test1' },
        { id: 2, novelty: true, offer: true, name: 'test2' },
        { id: 3, novelty: false, offer: true, name: 'test3' } 
        ],
      display: 'all',
      filters: [
        {novelty:'true'},
        {offer: 'true'}
      ]
    }
  }

  setCategory (category) {
    this.setState({
      display: category 
    });
  }

 render() {
   return(
   <div>
      <button onClick={()=>this.setCategory(true)}>Akce</button>
      <button onClick={()=>this.setCategory(true)}>Offer</button>
           {
      this.state.products.filter( product => 
       products.offer === this.state.display ||
        this.state.display==='all')
        .map(product =>
         <div>{product.name}</div>
           )
            }
   </div>
    )
  }
}

Answer 1

这是我提出的最终版本:

import React from 'react'

export default class extends React.Component {
  constructor() {
    super()

    this.state = {
      products: [
        { id: 1, novelty: true, offer: false, name: 'test1' },
        { id: 2, novelty: true, offer: true, name: 'test2' },
        { id: 3, novelty: false, offer: true, name: 'test3' } 
        ],
      filters: {
        novelty: true,
        offer: true
      }
    }
  }

  setCategory (category) {
    this.setState((state) => ({
      filters: Object.assign({}, state.filters, { [category]: !state.filters[category] })
    }));
  }

 render() {
   console.log(this.state.filters)
   return(
   <div>
      <button onClick={()=>this.setCategory('novelty')}>Akce</button>
      <button onClick={()=>this.setCategory('offer')}>Offer</button>
           { this.state.products
                       .filter(product => product.novelty === this.state.filters.novelty || product.offer === this.state.filters.offer)
                       .map(product =>
             <div key={product.id}>{product.name}</div>
           )}
   </div>
    )
  }
}

https://www.webpackbin.com/bins/-KpVHqfkjeraq6pGvHij

一些东西:

• 在您的情况下使用布尔值而不是字符串更适合.(true而不是'true').
• display: 'all'您的用例不是必需的.如果需要,您可以从过滤器中计算此值.
• setCategory收到category你想要设置为param的内容.
• 我会重命名setCategory为setFilter

另外,我正在使用asycnhronous版本setState.这允许您提交功能.

this.setState((state) => ({
      filters: Object.assign({}, state.filters, { [category]: !state.filters[category] })
}));

这里我Object.assign用来创建一个新的Object.我填充他, state.filters最后我更新你想要的过滤器. category将是novelty或者offer由于我正在使用速记版本[category].

总而言之,我还更新了你的filter功能,以检查product.novelty对抗filter.novelty或product.offer与filter.offer