Reactjs 数组长度在子组件的道具内返回零
itemsLength变量正在向分页组件返回零。分页组件上方的this.state.items.length显示计数为6,但在分页组件上显示为零Reactjs 数组长度在子组件的道具内返回零,reactjs,react-props,Reactjs,React Props,itemsLength变量正在向分页组件返回零。分页组件上方的this.state.items.length显示计数为6,但在分页组件上显示为零 {this.state.items.length} <Pagination itemsLength={this.state.items.length} currentPage={0} pageC
{this.state.items.length}
<Pagination
itemsLength={this.state.items.length}
currentPage={0}
pageCount={2}
/>
import React, { Component } from 'react';
class Pagination extends Component {
pageArray = [];
componentDidMount = () => {
console.log(this.props.itemsLength);
let { itemsLength, currentPage, pageCount } = this.props;
let pages = Math.ceil(itemsLength / pageCount);
console.log('itesm length ', itemsLength);
for (let i = 0; i < pages; i++) {
this.pageArray.push(i + 1);
}
console.log('page array ', this.pageArray);
}
render() {
return (
<div>
{
this.pageArray.map(
page => {
return (<button>page</button>);
}
)
}
</div>
);
}
}
export default Pagination;
这是父组件
{this.state.items.length}
<Pagination
itemsLength={this.state.items.length}
currentPage={0}
pageCount={2}
/>
import React, { Component } from 'react';
class Pagination extends Component {
pageArray = [];
componentDidMount = () => {
console.log(this.props.itemsLength);
let { itemsLength, currentPage, pageCount } = this.props;
let pages = Math.ceil(itemsLength / pageCount);
console.log('itesm length ', itemsLength);
for (let i = 0; i < pages; i++) {
this.pageArray.push(i + 1);
}
console.log('page array ', this.pageArray);
}
render() {
return (
<div>
{
this.pageArray.map(
page => {
return (<button>page</button>);
}
)
}
</div>
);
}
}
export default Pagination;
{this.state.items.length}
子分页组件
{this.state.items.length}
<Pagination
itemsLength={this.state.items.length}
currentPage={0}
pageCount={2}
/>
import React, { Component } from 'react';
class Pagination extends Component {
pageArray = [];
componentDidMount = () => {
console.log(this.props.itemsLength);
let { itemsLength, currentPage, pageCount } = this.props;
let pages = Math.ceil(itemsLength / pageCount);
console.log('itesm length ', itemsLength);
for (let i = 0; i < pages; i++) {
this.pageArray.push(i + 1);
}
console.log('page array ', this.pageArray);
}
render() {
return (
<div>
{
this.pageArray.map(
page => {
return (<button>page</button>);
}
)
}
</div>
);
}
}
export default Pagination;
import React,{Component}来自'React';
类分页扩展了组件{
pageArray=[];
componentDidMount=()=>{
console.log(this.props.itemsLength);
设{itemsLength,currentPage,pageCount}=this.props;
让pages=Math.ceil(itemsLength/pageCount);
console.log('itesm length',itemsLength);
for(设i=0;i{
返回(第页);
}
)
}
);
}
}
导出默认分页;
的sandbox链接我不认为代码有问题,可能是
codesandbox
原因,
- 当我更新
文件(可能还有任何其他文件)时,您有什么问题shop.jsx
- 但是,当我修改
文件并更新输出时,一切似乎都正常pagination.jsx