Reactjs useState加载状态未触发
我有一个组件,它接受数据,然后将其设置为XLSX。我想做的是,当我单击下载时,我想将加载设置为true,并显示加载指示或用户可以知道正在工作的内容。在我的代码下载工作,但当我点击按钮加载仍然是假的。为什么?Reactjs useState加载状态未触发,reactjs,Reactjs,我有一个组件,它接受数据,然后将其设置为XLSX。我想做的是,当我单击下载时,我想将加载设置为true,并显示加载指示或用户可以知道正在工作的内容。在我的代码下载工作,但当我点击按钮加载仍然是假的。为什么? import "antd/dist/antd.css"; import { Button } from "antd"; import { DownloadOutlined } from "@ant-design/icons"; import * as FileSaver from "file
import "antd/dist/antd.css";
import { Button } from "antd";
import { DownloadOutlined } from "@ant-design/icons";
import * as FileSaver from "file-saver";
import * as XLSX from "xlsx";
import React, {useState} from "react";
import moment from "moment";
const ExportToXlxs = ({ data }) => {
const [loading, setloading] = useState(false)
const exportData = () => {
setloading(true)
const fileType =
"application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8";
const fileExtension = ".xlsx";
let mappedData = [];
data.map((item) => {
return mappedData.push({
//make map
});
});
const ws = XLSX.utils.json_to_sheet(mappedData);
const wb = { Sheets: { data: ws }, SheetNames: ["data"] };
const excelBuffer = XLSX.write(wb, { bookType: "xlsx", type: "array" });
const data = new Blob([excelBuffer], { type: fileType });
FileSaver.saveAs(data, "file" + fileExtension);
setloading(false)
};
return loading ? <div>loading</div> : (
<Button
type="primary"
style={{
marginLeft: "50px",
alignSelf: "center",
}}
onClick={exportData}
icon={<DownloadOutlined />}
>
Download
</Button>
);
};
export default ExportToXlxs;
导入“antd/dist/antd.css”;
从“antd”导入{Button};
从“@ant design/icons”导入{DownloadOutlined}”;
从“文件保存程序”导入*作为文件保存程序;
从“XLSX”导入*作为XLSX;
从“React”导入React,{useState};
从“时刻”中导入时刻;
const ExportToXlxs=({data})=>{
常量[loading,setloading]=useState(false)
const exportData=()=>{
设置加载(真)
常量文件类型=
“application/vnd.openxmlformats of icedocument.spreadsheetml.sheet;charset=UTF-8”;
const fileExtension=“.xlsx”;
设mappedData=[];
data.map((项目)=>{
返回mappedData.push({
//制作地图
});
});
const ws=XLSX.utils.json_到_表(mappedData);
const wb={Sheets:{data:ws},SheetNames:[“data”]};
constExcelBuffer=XLSX.write(wb,{bookType:“XLSX”,type:“array”});
const data=new Blob([excelBuffer],{type:fileType});
FileSaver.saveAs(数据,“文件”+文件扩展名);
设置加载(错误)
};
返回装载?装载:(
下载
);
};
导出默认的exportToxlx;
您可以这样做,分别调用setstate
import "antd/dist/antd.css";
import { Button } from "antd";
import { DownloadOutlined } from "@ant-design/icons";
import * as FileSaver from "file-saver";
import * as XLSX from "xlsx";
import React, {useState} from "react";
import moment from "moment";
const ExportToXlxs = ({ data }) => {
const [loading, setloading] = useState(false)
const exportData = () => {
const fileType =
"application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8";
const fileExtension = ".xlsx";
let mappedData = [];
data.map((item) => {
return mappedData.push({
//make map
});
});
const ws = XLSX.utils.json_to_sheet(mappedData);
const wb = { Sheets: { data: ws }, SheetNames: ["data"] };
const excelBuffer = XLSX.write(wb, { bookType: "xlsx", type: "array" });
const data = new Blob([excelBuffer], { type: fileType });
FileSaver.saveAs(data, "file" + fileExtension);
setloading(false)
};
return loading ? <div>loading</div> : (
<Button
type="primary"
style={{
marginLeft: "50px",
alignSelf: "center",
}}
onClick={()=>{
setloading(true);
exportData();
}
icon={<DownloadOutlined />}
>
Download
</Button>
);
};
export default ExportToXlxs;
导入“antd/dist/antd.css”;
从“antd”导入{Button};
从“@ant design/icons”导入{DownloadOutlined}”;
从“文件保存程序”导入*作为文件保存程序;
从“XLSX”导入*作为XLSX;
从“React”导入React,{useState};
从“时刻”中导入时刻;
const ExportToXlxs=({data})=>{
常量[loading,setloading]=useState(false)
const exportData=()=>{
常量文件类型=
“application/vnd.openxmlformats of icedocument.spreadsheetml.sheet;charset=UTF-8”;
const fileExtension=“.xlsx”;
设mappedData=[];
data.map((项目)=>{
返回mappedData.push({
//制作地图
});
});
const ws=XLSX.utils.json_到_表(mappedData);
const wb={Sheets:{data:ws},SheetNames:[“data”]};
constExcelBuffer=XLSX.write(wb,{bookType:“XLSX”,type:“array”});
const data=new Blob([excelBuffer],{type:fileType});
FileSaver.saveAs(数据,“文件”+文件扩展名);
设置加载(错误)
};
返回装载?装载:(
{
设置加载(真);
exportData();
}
图标={}
>
下载
);
};
导出默认的exportToxlx;
您正在exportData
函数中运行异步操作。尝试将其更新到以下位置:
const exportData = async () => {
setloading(true)
const fileType =
"application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8";
const fileExtension = ".xlsx";
let mappedData = [];
data.map((item) => {
return mappedData.push({
//make map
});
});
const ws = await XLSX.utils.json_to_sheet(mappedData);
const wb = { Sheets: { data: ws }, SheetNames: ["data"] };
const excelBuffer = await XLSX.write(wb, { bookType: "xlsx", type: "array" });
const data = new Blob([excelBuffer], { type: fileType });
await FileSaver.saveAs(data, "file" + fileExtension);
setloading(false)
};
现在,您的操作将在需要的地方等待,然后再异步运行其他操作,如setload
。基本上,您的setLoading
函数将在不等待文件保存的情况下快速运行。请参阅@vinayakshahdeo对您的问题的评论
注意:我添加的一些
wait
关键字可能不是必需的。我不太熟悉您正在使用的库。这是一个内部异步调用,用于更新状态,因此当您设置加载状态时,它在开始时为true,然后在上一个调用完成之前变为false,如果您可以共享沙盒,usestate将加载设置为false。我可以发布正确答案。共享代码沙盒链接我们will Check这不会阻止设置加载
在导出数据
函数中立即变回false
。@BarryMichaelDoyle我检查了他的数据是否太小,无论我们做什么,都会处理得非常快这些解决方案中的一个可能你有带wokring的codepen?你确定你添加了async
中的关键字?