uniapp读取和写入文件

注意事项：扫码页读取文件时，先把data.txt文件放入手机内（eqp/data.txt），再用调试基座扫码筛选出数据打印出来；盘点页：可以先扫码，每次扫码都会写入文件(records/data.txt),返回上一页时，再次进入此页面，先读取已经有的文件内容，扫码写入此文件。查找时，可断开数据线，再次连接数据线，在手机内存中找，看是否写入文件，核实一下。后端会把这个文件内容导入数据，同时删掉此文件。（先读再写的好处：盘点时中途休息或手机没电）

1，扫码页：读取手机内存中放入的文件，把符合条件的筛选出来，渲染页面

// An highlighted block
<template>
	<view class="flex align-center justify-center">
		<view class="flex align-center btn-view-top">
			<view class="flex align-center flex-column" style='margin-right: 200rpx;' @tap='scanTap'>
				<view class="text">资产扫码</view>
			</view>
			<view class="flex align-center flex-column" @tap='goPageTap'>
				<view class="text">盘点</view>
			</view>
		</view>
	</view>
</template>

<script>
	//引入读取方法
	import {getJsonData} from '@/common/convertFormat.js';
export default {
	data() {
		return {
			dataObj:null
		};
	},
	onLoad(options) {
		this.readFiles()
		
	},
	
	methods: {
		async readFiles(){
			const pathUrl = 'eqp/data.txt';
			let res = await getJsonData(pathUrl);
			// console.log('读取-----',JSON.parse(res))
			this.dataObj = JSON.parse(res);
			// console.log('读取文件===----',this.dataList)
			
		},
		scanTap(){
			let that = this;
			uni.scanCode({
				success(res){
					let eqpCode = res.result;
					let obj = that.dataObj[eqpCode];
					console.log('====',obj)
	
				}
			})
		},
		
	}
};
</script>
<style>
	page{
		background-color: white;
	}
</style>
<style lang="scss" scoped>
page {
	background-color: white;
	.btn-view-top{
		margin-top: 400rpx;
	}
	.img{
		width: 90rpx;
		height: 90rpx;
	}
	.text{
		font-size: 27rpx;
		margin-top: 10rpx;
	}
}
</style>

2，盘点页：先读取手机文件，扫码写入该文件

// An highlighted block
<!-- 盘点 -->
<template>
	<view>
		<u-navbar back-icon-color="#699AEB" :is-back="false" title="" :is-fixed="true" :border-bottom="false" :background="background">
			<view class="slot-wrap">
				<view class="flex align-center justify-between px-3">
					<image class="leftIcon" src="/static/customer/left-icon.png" mode="aspectFill" @tap="clickLeft"></image>
					<view class="titles">盘点</view>
					<image src="/static/equipment/scan.png"  class="befite-01 mr-4"  mode="widthFix" @tap.stop='scanTap'></image>
				</view>
			</view>
		</u-navbar>
		<!-- <view>{{dataList}}</view> -->
		<view class="contents" >
			<!-- <scroll-view
				scroll-y="true"
				:style="{ height: scrollHeight+ 'px' }"> -->
				<view  style='padding-top: 30rpx;' v-if="dataList.length>0">
					<view class="card" v-for="(v,idx) in dataList" :key="idx">
						<view class="flex align-center"><view class="index">{{idx+1}}</view></view>
						<view class="">【盘点编码】{{v.eqpCode}}</view>
						<view class='mt-2'>【盘点时间】{{v.checkTime || '无'}}</view>
					</view>
				</view>
				<!-- <no-data  title="暂无数据" v-else></no-data> -->
			<!-- </scroll-view> -->
		</view>
		<!-- <view class="footer">
			<view class="btn" @tap='submitTap'>上 传</view>
		</view> -->
		
	</view>
</template>

<script>
	import {getNowDate} from '@/common/checkUtil.js';
	import {changeData,getJsonData} from '@/common/convertFormat.js';
	
	export default{
		data(){
			return{
				background: {
					backgroundColor: '#FFFFFF'
				},
				scrollHeight:0,
				uuid:null,
				dataList:[],
				
			}
		},
		onReady() {
			// this.calcScrollHeight();
		},
		onLoad() {
			const _self = this;
			plus.device.getInfo({
				success(e){
					_self.uuid = JSON.stringify(e.uuid);
					console.log(_self.uuid)
				}
			});
			console.log(this.uuid)
			// const res = uni.getStorageSync('resObj');
			// if (res.data) this.dataList = res.data
			// console.log('---',this.dataList)
			 this.readFiles();
		},
		
		
		methods:{
			async readFiles(){
				const pathUrl = 'records/data.txt';
				let res = await getJsonData(pathUrl);
				let obj = JSON.parse(res);
				// console.log('读取文件===',obj)
				if(obj.data.length>0) this.dataList = obj.data;
			},
			calcScrollHeight() {
				let that = this;
				uni.getSystemInfo({
					success(res) {
						let windowH = res.windowHeight;
						let info = uni.createSelectorQuery().select('.footer');
						info.boundingClientRect(function(data) {
							let topH = data.height;
							that.scrollHeight = windowH - topH - 108;
						}).exec();
					   
					}
				});
			},
			scanTap(){
				let that = this;
				uni.scanCode({
					success(res){
						// console.log('盘点扫码===',res)
						
						 if(res.result){
							
					that.dataList.push({eqpCode:res.result,checkTime:getNowDate()});
							//未改之前：每次扫码本地保存，不在扫码方法调用扫码，点上传按钮，写入文件并清空本地保存。在进入页面onLoad时，先获取本地保存，再扫码
							// that.$forceUpdate();
							// let obj = {
							// 	"data":that.dataList
							// }
						   //	uni.setStorageSync('resObj',obj);
							// uni.showToast({
							// 	title: '盘点成功',
							// 	icon: 'success'
							// });
							
							//写入文件
							let data = {
								scanEqpCode:that.uuid,
								data:that.dataList
							}
							// console.log('data---',data)
							const pathUrl = 'records/data.txt';
							changeData(pathUrl, 0,data);
							// that.readFiles();
							that.scanTap();
						}
					}
				})
			},
			
			clickLeft() {
				uni.navigateBack({
					delta: 1
				});
			},
			
			
			// submitTap(){
			// 	if(this.dataList.length==0){
			// 		uni.showToast({
			// 			title: '请扫码',
			// 			icon: 'none'
			// 		});
			// 	}else{
					
			// 		let data = {
			// 			scanEqpCode:this.uuid,
			// 			data:this.dataList
			// 		}
					
			// 		const pathUrl = 'records/data.txt';
			// 		changeData(pathUrl, 0,data);
			// 		uni.showToast({
			// 			title: '上传成功',
			// 			icon: 'success'
			// 		});
			// 		this.dataList = [];
			// 		 uni.removeStorageSync('resObj');
			// 	}
			// }
		},
		
	}
</script>

<style>
page {
	background-color: #f6f7fb;
}
</style>
<style lang="scss" scoped>
	page {
		width: 100%;
		height: 100%;
		background-color: #f6f7fb;
		.leftIcon {
			width: 17rpx;
			height: 30rpx;
		}
		.titles {
			width: 640rpx;
			padding: 0 20rpx;
			font-weight: 600;
			font-size: 28rpx;
			text-align: center;
		}
		.befite-01 {
			width: 50rpx;
			height: 50rpx;
		}
		
		.right-icon{
			width: 14rpx;
			height: 14rpx;
			margin-left: 16rpx;
		}
		.black{
			color: black;
		}
		.grey{
			color: #c3c3c3;
		}
		.footer {
			position: fixed;
			bottom: 0;
			left: 0;
			right: 0;
			padding: 30rpx 34rpx;
			background: #ffffff;
			box-shadow: 0rpx 4rpx 11rpx 2rpx rgba(62, 62, 62, 0.17);
			.btn {
				margin: 0 auto;
				width: 690rpx;
				height: 80rpx;
				line-height: 80rpx;
				text-align: center;
				background: #588fe9;
				border-radius: 45rpx;
				font-size: 28rpx;
				font-weight: 500;
				color: #ffffff;
			}
		}
		
		.contents{
			margin-left:28rpx;
			margin-right: 26rpx;
			margin-top: 30rpx;
			background: #ffffff;
			border-radius: 16rpx;
			
			.card{
				padding: 0rpx 30rpx 30rpx;
				margin-bottom: 30rpx;
				font-size: 26rpx;
				color: #787B8B;
				border-bottom: 1rpx solid #f6f7fb;
				.index{
					padding: 4rpx 10rpx;
					background: #F2F6FE;
					border-radius: 20%;
					font-size: 26rpx;
					font-weight: 600;
					color: #4B8EF0;
					margin-bottom: 20rpx;
				}
				.select-img {
					width: 33rpx;
					height: 33rpx;
					margin-right: 10rpx;
				}
				.bottom-view{
					border-top: 1rpx solid #eee;
					margin-top: 30rpx;
					padding-top: 30rpx;
					.btn-view{
						padding: 10rpx 40rpx;
						border-radius: 10rpx;
						background-color: #4B8EF0;
						color: white;
					}
				}
				
				
			}
		}
	}
</style>

3，放在手机eqp文件夹下面的data.txt文件内容

//数据线连接电脑传送文件：此电脑\HUAWEI P30\内部存储\Android\data\com.dianwang.mes\downloads\eqp
//包名com.dianwang.mes
//调试基座 io.dcloud.HBuilder

// An highlighted block
{"EQP1539546740871532544":{"brand":"622测试设备3","eqpCode":"EQP1539546740871532544","eqpModel":"622测试设备3","eqpName":"622测试设备3","id":"1539546740869046274","locationName":"蒽醌一车间"},"EQP1541672639645487104":{"eqpCode":"EQP1541672639645487104","eqpName":"628测试设备","id":"1541672639814270977","locationName":"一楼北"},"EQP1550030826174025728":{"brand":"721资产","eqpCode":"EQP1550030826174025728","eqpModel":"721资产","eqpName":"721资产","id":"1550030826213539841","locationName":"蒽醌一车间"},"EQP1542760718493945856":{"brand":"111","deptName":"设备部","eqpCode":"EQP1542760718493945856","eqpModel":"L","eqpName":"设备刘","id":"1542760718504099841","locationName":"二楼西北"},"0101V01ceshi1":{"eqpCode":"0101V01ceshi1","eqpName":"纯水槽测试1","id":"1540166541860249602","locationName":"一线车间"},"0113R99999":{"eqpCode":"0113R99999","eqpModel":"10","eqpName":"可以导入","id":"1542802363341668354","locationName":"四楼西北"},"0101V088":{"eqpCode":"0101V088","eqpName":"缓冲罐","id":"1541353353916719105","locationName":" 测试四车间"},"0101V066":{"eqpCode":"0101V066","eqpName":"缓冲罐","id":"1541353353849610245","locationName":"三楼"},"0101V044":{"eqpCode":"0101V044","eqpName":"缓冲罐","id":"1541353353849610243","locationName":"二楼北"},"0101V022":{"eqpCode":"0101V022","eqpName":"缓冲罐","id":"1541353353849610241","locationName":"二楼西"},"0101V023":{"eqpCode":"0101V023","eqpName":"缓冲罐","id":"1541353353849610242","locationName":"一楼西"},"0101V01":{"eqpCode":"0101V01","eqpName":"纯水槽","id":"1539549663652294658","locationName":"一线车间"},"0113R107":{"eqpCode":"0113R107","eqpModel":"3","eqpName":"活性炭打浆釜","id":"1542088258313347075","locationName":"一楼西北"},"0113R305":{"eqpCode":"0113R305","eqpModel":"8","eqpName":"水解釜","id":"1542088258250432513","locationName":"三楼西南","remark":"单端面机封204JT-110"},"0101V02ceshi2":{"eqpCode":"0101V02ceshi2","eqpName":"纯水槽测试2","id":"1540166541860249603","locationName":"一线车间"},"0101V02":{"eqpCode":"0101V02","eqpName":"缓冲罐","id":"1539549663664877569","locationName":"四楼西北"},"0113R106":{"eqpCode":"0113R106","eqpModel":"3","eqpName":"氯化钙溶解釜","id":"1542088258313347074","locationName":"一楼西北"},"EQP1539546497513820160":{"brand":"622测试设备2","eqpCode":"EQP1539546497513820160","eqpModel":"622测试设备2","eqpName":"622测试设备2","id":"1539546497511333890","locationName":"蒽醌一车间"},"0113R7627":{"eqpCode":"0113R7627","eqpName":"7月4日导入设备","id":"1543779187847864322","locationName":"四楼西北","remark":"暂无"},"0113R101":{"eqpCode":"0113R101","eqpModel":"15","eqpName":"稀释釜","id":"1542088258250432514","locationName":"一楼西南","remark":"单端面机封204JT-125"},"EQP1542793745408331776":{"deptName":"日兴生物科技","eqpCode":"EQP1542793745408331776","eqpModel":"M","eqpName":"刘钦的设备","id":"1542793745414291457","locationName":"三楼西北"},"0113R105":{"eqpCode":"0113R105","eqpModel":"30","eqpName":"盐析釜","id":"1542088258313347073","locationName":"一楼西北"},"0113R303":{"eqpCode":"0113R303","eqpModel":"5","eqpName":"溴化釜","id":"1542088258179129347","locationName":"三楼西北","remark":"双端面机封221-95"},"0113R104":{"eqpCode":"0113R104","eqpModel":"45","eqpName":"中和釜","id":"1542088258250432517","locationName":"一楼西北"},"0113R302":{"eqpCode":"0113R302","eqpModel":"10","eqpName":"磺化釜","id":"1542088258179129346","locationName":"三楼西北","remark":"双端面机封221-110"},"0113R401":{"eqpCode":"0113R401","eqpModel":"10","eqpName":"分层釜","id":"1542088258103631874","locationName":"四楼西北"},"EQP1539546040905109504":{"brand":"622测试设备","deptName":"日兴生物科技","eqpCode":"EQP1539546040905109504","eqpModel":"622测试设备","eqpName":"622测试设备","id":"1539546040906817537","locationName":"蒽醌一车间"},"0113R103":{"eqpCode":"0113R103","eqpModel":"30","eqpName":"一精釜","id":"1542088258250432516","locationName":"一楼西南"},"0113R301":{"eqpCode":"0113R301","eqpModel":"10","eqpName":"磺化釜","id":"1542088258179129345","locationName":"三楼西北","remark":"双端面机封221-110"},"0113R201":{"eqpCode":"0113R201","eqpModel":"5","eqpName":"配酸釜","id":"1542088258313347076","locationName":"二楼西北"},"0113R102":{"eqpCode":"0113R102","eqpModel":"30","eqpName":"二精釜","id":"1542088258250432515","locationName":"一楼西南"},"EQP1540163441451470848":{"eqpCode":"EQP1540163441451470848","eqpName":"624测试设备2","id":"1540163441405566977","locationName":"蒽醌一车间"},"EQP1540159981989531648":{"brand":"624测试设备","deptName":"日兴生物科技","eqpCode":"EQP1540159981989531648","eqpModel":"624测试设备","eqpName":"624测试设备","id":"1540159982191091713","locationName":"一线汽化间"},"0101V077":{"eqpCode":"0101V077","eqpName":"缓冲罐","id":"1541353353849610246","locationName":"测试三车间"},"0101V055":{"eqpCode":"0101V055","eqpName":"缓冲罐","id":"1541353353849610244","locationName":"测试三车间"},"0101V011":{"eqpCode":"0101V011","eqpName":"纯水槽","id":"1541353353824444418","locationName":"一楼北"},"EQP1539489933109104640":{"eqpCode":"EQP1539489933109104640","eqpName":"110","id":"1539489933110812673","locationName":"蒽醌一车间"},"0113":{"deptName":"生产部","eqpCode":"0113","eqpName":"分层釜","id":"1537075241819504642","locationName":"四楼西北"},"0113R999":{"deptName":"日兴生物科技","eqpCode":"0113R999","eqpModel":"10","eqpName":"感冒灵测试","id":"1542723508735426561","locationName":"四楼西北"},"EQP1550753570918371328":{"brand":"723设备","eqpCode":"EQP1550753570918371328","eqpModel":"723设备","eqpName":"723设备","id":"1550753570957873154","locationName":"蒽醌一车间"}}

4，封装获取当前时间的方法

// 路径 /common/checkUtil.js
// 获取系统当前时间
export function getNowDate() {
	var nowdate = new Date();
	var Y = nowdate.getFullYear();
	var M = (nowdate.getMonth() + 1)<10?'0'+(nowdate.getMonth() + 1):(nowdate.getMonth() + 1);
	var D = nowdate.getDate()<10?'0'+nowdate.getDate():nowdate.getDate();
	var h = nowdate.getHours()<10?'0'+nowdate.getHours():nowdate.getHours();
	var m = nowdate.getMinutes()<10?'0'+nowdate.getMinutes():nowdate.getMinutes();
	var s = nowdate.getSeconds()<10?'0'+nowdate.getSeconds():nowdate.getSeconds();
	var formatnowdate = Y + '-' + M + '-' + D + ' ' + h + ':' + m + ':' + s

	return formatnowdate
}

5，封装读取写入方法

// 路径：/common/convertFormat.js
// 读取json文件
function getJsonData(path) { //path:路径
	
	return new Promise(resolve => { 
		plus.io.requestFileSystem(plus.io.PUBLIC_DOWNLOADS, fs => { //请求文件系统
				fs.root.getFile(
					path, {   
						create: true //当文件不存在时创建
					}, fileEntry => {
						fileEntry.file(function(file) {
							let fileReader = new plus.io
								.FileReader(); //new一个可以用来读取文件的对象fileReader
							fileReader.readAsText(file, "utf-8"); //读文件的格式
							fileReader.onerror = e => { //读文件失败
								// console.log("获取文件失败", fileReader.error);
								plus.nativeUI.toast("获取文件失败,请重启应用", {
									background: "#ffa38c",
								});
								return;
							};
							fileReader.onload = e => { //读文件成功
								// console.log("读取文件成功");
								let txtData = e.target.result;
								resolve(txtData);    
								// 回调函数内的值想返回到函数外部  就用promise+resolve来返回出去
							};
						});
					}, error => {
						console.log("2新建获取文件失败", error);
						plus.nativeUI.toast("获取文件失败,请重启应用", {
							background: "#ffa38c",
						});
						return;
					});
			},
			e => {
				console.log("1请求文件系统失败", e.message);
				plus.nativeUI.toast("请求系统失败,请重启应用", {
					background: "#ffa38c",
				});
				return;
			}
		);
	});
};
// 写入josn文件
function changeData(path, seek, writeData) { //参数1：上传路径，参数2：seek方法可设置文件操作指定位置，参数3：写入的json数据
	return new Promise(resolve => {
		plus.io.requestFileSystem(plus.io.PUBLIC_DOWNLOADS, fs => {
			fs.root.getFile(path, {
					create: true
				}, fileEntry => {
					fileEntry.file(file => {
						fileEntry.createWriter(writer => {
								plus.nativeUI.showWaiting("正在保存信息");
								writer.seek(seek); //覆盖文件
								const writeDataTemp = JSON.stringify(writeData, null,
									"\r").replace(/[\r]/g, "");
								writer.write(writeDataTemp); // 整个文件重写
								writer.onerror = function() {
									console.log("4写入文件失败", writer.error.message);
									plus.nativeUI.closeWaiting();
									plus.nativeUI.toast("修改信息失败,请重新操作", {
										background: "#ffa38c",
									});
									return;
								};
								writer.onsuccess = function() { //填写文件成功
									plus.nativeUI.closeWaiting();
									plus.nativeUI.toast("盘点成功", {
										background: "rgba(255, 255, 255, 0.6)",
									});
									resolve("1");
								};
							},
							error => {
								console.log("3创建creactWriter失败", error);
								plus.nativeUI.toast("保存文件失败,请重新操作", {
									background: "#ffa38c",
								});
								return;
							});
					});
				},
				error => {
					console.log("2获取文件失败", error);
					plus.nativeUI.toast("保存文件失败,请重新操作", {
						background: "#ffa38c",
					});
					return;
				}
			);
		}, e => {
			console.log("1请求文件系统失败", e.message);
			plus.nativeUI.toast("请求系统失败,请重新操作", {
				background: "#ffa38c",
			});
			return;
		});
	});
}

async function saveFile(url, file, newfilename) {
	let c = await creatDirs(url)
	let isokm = moveDirectyOrFile(file, url + "/", newfilename);
	return isokm
}
//循环创建目录 url:"_doc/...."  _doc开头
async function creatDirs(url) {
	let urllist = url.split("/");
	console.log(urllist)
	//创建文件夹
	let u = "";
	for (let i = 0; i < urllist.length - 1; i++) {
		let j = i;
		if (i == 0) {
			u = urllist[i];
		} else {
			u = u + "/" + urllist[i];
		}
		console.log(i + "-------------------")
		console.log(u)
		console.log(urllist[j + 1])
		await CreateNewDir(u, urllist[j + 1]);
	}
}
//重命名目录或文件名
function moveDirectyOrFile(srcUrl, dstUrl, newName) { //srcUrl需要移动的目录或文件，dstUrl要移动到的目标目录（父级）
	plus.io.resolveLocalFileSystemURL(srcUrl, function(srcEntry) {
		//console.log(111)
		plus.io.resolveLocalFileSystemURL(dstUrl, function(dstEntry) {
			//console.log(222)
			if (srcEntry.isDirectory) {
				//console.log(33)
				srcEntry.moveTo(dstEntry, newName, function(entry) {
					//console.log("New Path: " + entry.fullPath);
					return true;
				}, function(e) {
					return e;
					//console.log(e.message);
				});
			} else {
				srcEntry.moveTo(dstEntry, newName, function(entry) {
					//console.log("New Path: " + entry.fullPath);
					return true;
				}, function(e) {
					return e;
					//console.log(e.message);
				});
			}
		}, function(e) {
			uni.showToast({
				title: '获取目标目录失败:' + e.message,
				duration: 2000,
				icon: 'none'
			});
		});
	}, function(e) {
		uni.showToast({
			title: '获取目录失败:' + e.message,
			duration: 2000,
			icon: 'none'
		});
	});
}

//创建一个新目录
function CreateNewDir(url, dirName) {
	//url值可支持相对路径URL、本地路径URL
	return new Promise((resolver, reject) => {
		plus.io.resolveLocalFileSystemURL(url, function(entry) {
			entry.getDirectory(dirName, {
				create: true,
				exclusive: false
			}, function(dir) {
				resolver(true)
			}, function(error) {
				reject(error.message)
				uni.showToast({
					title: dirName + '目录创建失败:' + error.message,
					duration: 2000,
					icon: 'none'
				});
			});
		}, function(e) {
			reject(error.message)
			uni.showToast({
				title: '获取目录失败:' + e.message,
				duration: 2000,
				icon: 'none'
			});
		});
	})
}


function copyFileTo(url, newUrl, dirName, newName) {
	if (url.length >= 7 && "file://" == url.substring(0, 7)) {
		url = url.substring(7)
	}
	let tempUrl = url.substring(0, url.lastIndexOf('/'));
	let addUrl = newUrl + '/' + dirName;
	console.log(addUrl, tempUrl)
	if (addUrl == tempUrl) {
		return url;
	}
	console.log(newUrl, dirName, newName)
	return new Promise((resolve, reject) => {
		plus.io.resolveLocalFileSystemURL(url, async (entry) => {
			if (entry.isFile) {
				let c = await CreateNewDir(newUrl, dirName)
				let u = await getDirsys(addUrl)
				entry.copyTo(u, newName, en => {
					resolve(en.fullPath);
				}, e => {
					console.log(e);
					reject('错误：复制时出现错误')
					uni.showModal({
						title: "错误",
						content: "复制时出现错误"
					})
				})
			} else {
				reject('错误：路径必须是文件')
				uni.showModal({
					title: "错误",
					content: "路径必须是文件"
				})
			}
		}, (e) => {
			console.log(e);
			reject(e)
			uni.showModal({
				title: "错误",
				content: "打开文件系统时出错"
			})
		});
	})
}
//获取目录对象
function getDirsys(url) {
	return new Promise((resolve, reject) => {
		plus.io.resolveLocalFileSystemURL(url, (entry) => {
			resolve(entry)
		}, (e) => {
			reject(e)
			console.log(e);
		});
	})
}
//将这些方法暴露出去
export {
	getJsonData,
	changeData,
	saveFile,
	creatDirs,
	moveDirectyOrFile,
	copyFileTo,
	getDirsys,
};

6，扫的二维码