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Javascript react无法设置未定义道具的属性_Javascript_Reactjs - Fatal编程技术网

Javascript react无法设置未定义道具的属性

Javascript react无法设置未定义道具的属性,javascript,reactjs,Javascript,Reactjs,我有一个像这样的简单组件 import { Component } from 'react' export default class SearchList extends Component(){ constructor(props){ super(props); } render(){ const { placeholder } = this.props; return( <div cla

我有一个像这样的简单组件

import { Component } from 'react'

export default class SearchList extends Component(){
    constructor(props){
        super(props);
    }
    render(){
        const { placeholder } = this.props;
        return(
            <div className="searchList">
                <input type="text" placeholder={placeholder}/>
                <button>Search</button>
            </div>
        )
    }
}
从'react'导入{Component}
导出默认类SearchList扩展组件(){
建造师(道具){
超级(道具);
}
render(){
const{placeholder}=this.props;
返回(
搜寻
)
}
}
我在某处做的事


为什么我出现了无法设置未定义道具属性的错误?

当您编写一个扩展
react.component
的react组件时,您不需要在
react.component
之后额外的
()

用这个

export default class SearchList extends Component{
    constructor(props){
        super(props);
    }
    render(){
        const { placeholder } = this.props;
        return(
            <div className="searchList">
                <input type="text" placeholder={placeholder}/>
                <button>Search</button>
            </div>
        )
    }
}
导出默认类SearchList扩展组件{
建造师(道具){
超级(道具);
}
render(){
const{placeholder}=this.props;
返回(
搜寻
)
}
}

export default class SearchList extends Component()中的remove(),哎哟,真是个粗心的错误。