json - 如何在 React 中从我的 json 中删除重复值
问题描述
我正在使用 React 开发应用程序,但遇到了问题。我从 json 中提取了一个值,并且重复了这些值。我只希望每个值出现一次。
我希望它只返回一次“Padre”的每个元素:“CRM”、“Permisos”和“Telefonia”。“Hijo”也是如此。
我尝试将“.concat”更改为“.reduce”,因为我读过它可以像这样完成,但它不起作用。我看过一些例子,但没有一个适用于“this.state”,所以我不知道该怎么做。
你能帮我用正确的方法吗?
这是我的 json 文件的一部分
[
{
"Id":"114",
"Padre":"CRM",
"Hijo":"Argumentarios"
},
{
"Id":"115",
"Padre":"CRM",
"Hijo":"Argumentarios"
},
{
"Id":"116",
"Padre":"CRM",
"Hijo":"Argumentarios"
},
{
"Id":"44",
"Padre":"Permisos",
"Hijo":"root"
},
{
"Id":"45",
"Padre":"Permisos",
"Hijo":"root"
},
{
"Id":"46",
"Padre":"Permisos",
"Hijo":"root"
},
{
"Id":"47",
"Padre":"Permisos",
"Hijo":"root"
},
{
"Id":"50",
"Padre":"Telefonia",
"Hijo":"Audio"
},
{
"Id":"51",
"Padre":"Telefonia",
"Hijo":"Audio"
},
{
"Id":"52",
"Padre":"Telefonia",
"Hijo":"Configuracion"
},
{
"Id":"70",
"Padre":"Telefonia",
"Hijo":"Rutas"
}
]
出于保密原因,我无法显示实际文件。在我的下一个代码中,我更改了假 json url 的获取
我用@Avanthika 和@blaz 代码编辑我的代码。目前该代码有效,但仅显示它找到的“父亲”和“儿子”的第一个值。我只需要显示一次“父亲”和“儿子”的不同值。示例结果: 父亲:CRM PERMISOS 儿子:ARGUMENTARIOS ROOT
目前,我只看到我的新代码:CRM (Padre) 和 Argumentarios (Son)。其余元素未显示。
import React, { Component } from 'react';
class Nav extends Component{
constructor(props){
super(props)
this.state = {
menuSubmenu:[]
}
}
componentWillMount(){
fetch('http://FAKE.php')
.then(response => response.json())
.then(menuSubmenu =>{
menuSubmenu.forEach(datos => {
let data = {
menu:datos.Padre,
submenu:datos.Hijo,
id:datos.Id
}
//console.log( data )
//console.log (data.menu);
this.setState({
menuSubmenu:this.state.menuSubmenu.concat([data])
})
})
})
}
render() {
const array = [...this.state.menuSubmenu];
const distinctValues = array.filter(
({ Padre, Hijo }, index) => {
return array.findIndex(item => item.Padre === Padre && item.Hijo === Hijo) === index;
});
//console.log(this.state.menuSubmenu);
//console.log(distinctValues);
if (distinctValues.length > 0) {
return(
<div>
{distinctValues.map(datos => <Navegacion key={datos.id} menu={datos.menu} submenu={datos.submenu} />)}
</div>
);
}
return (<p>Cargando usuarios...</p>);
}
}
class Navegacion extends Component{
render(){
return (
<ul className="list">
<li className="list__item">{this.props.menu}
<ul className="list">
<li className="list__item">
<a href="#">{this.props.submenu}</a>
</li>
</ul>
</li>
</ul>
)
}
}
export default Nav;
这张图片是我的 json 的结果。我的 json 结果
我希望你能帮助我使用“减少”功能。非常感谢!
解决方案
- 您可以使用 new Set 来使 Padre 和 Hijo 的数组列表独一无二。
const array = [{"Id":"114","Padre":"CRM","Hijo":"Argumentarios"},
{"Id":"115","Padre":"CRM","Hijo":"Argumentarios"},
{"Id":"116","Padre":"CRM","Hijo":"Argumentarios"},
{"Id":"44","Padre":"Permisos","Hijo":"root"},
{"Id":"45","Padre":"Permisos","Hijo":"root"},
{"Id":"46","Padre":"Permisos","Hijo":"root"},
{"Id":"47","Padre":"Permisos","Hijo":"root"},
{"Id":"50","Padre":"Telefonia","Hijo":"Audio"},
{"Id":"51","Padre":"Telefonia","Hijo":"Audio"},
{"Id":"52","Padre":"Telefonia","Hijo":"Configuracion"},
{"Id":"70","Padre":"Telefonia","Hijo":"Rutas"}];
const distinctValues = Array.from(new Set(array.map(elem => `${elem.Padre}-${elem.Hijo}`))).map(distinctVal => {
const [ Padre, Hijo ] = distinctVal.split("-");
return ({
Id: array.find(elem => elem.Padre === Padre && elem.Hijo === Hijo).Id,
Padre,
Hijo
});
});
console.log(distinctValues);
- 或者您可以使用前面提到的 lodash 来提取 uniq 值。您必须使用 uniqBy。
const array = [{"Id":"114","Padre":"CRM","Hijo":"Argumentarios"},
{"Id":"115","Padre":"CRM","Hijo":"Argumentarios"},
{"Id":"116","Padre":"CRM","Hijo":"Argumentarios"},
{"Id":"44","Padre":"Permisos","Hijo":"root"},
{"Id":"45","Padre":"Permisos","Hijo":"root"},
{"Id":"46","Padre":"Permisos","Hijo":"root"},
{"Id":"47","Padre":"Permisos","Hijo":"root"},
{"Id":"50","Padre":"Telefonia","Hijo":"Audio"},
{"Id":"51","Padre":"Telefonia","Hijo":"Audio"},
{"Id":"52","Padre":"Telefonia","Hijo":"Configuracion"},
{"Id":"70","Padre":"Telefonia","Hijo":"Rutas"}];
const distintValues = _.uniqBy(array, elem => [elem.Padre, elem.Padre].join());
console.log(distintValues);
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js"></script>
您需要以这种方式修复解决方案:
render() {
const array = [...this.state.menuSubmenu];
// Put the solution you like here.
// const distinctValues = the solution you like
if (distinctValues.length > 0) {
return(
<div>
{distinctValues.map(datos => <Navegacion key={datos.id} menu={datos.menu} submenu={datos.submenu} />)}
</div>
);
}
return (<p>Cargando usuarios...</p>);
}