Net Core 使用Mongodb操作文件（上传，下载）
1.Mongodb GridFS 文件操作帮助类。
GridFS 介绍 https://baike.baidu.com/item/GridFS/6342715?fr=aladdin
DLL源码：https://gitee.com/chenjianhua1985/mongodb-client-encapsulation
DLL文件：链接：https://pan.baidu.com/s/1SpWDtaXjavalJQav89UE4A?pwd=yceu 提取码：yceu
/// <summary>/// MongoDB 文件 操作类/// </summary>public abstract class MongoFileRepository : IMongoFileRepository{#region GridFS 介绍// MongodB使用两个集合来存储GridFS文件，一个是fs.files，另一个是fs.chunks// fs.files这个集合中存储的是每一个上传到数据库的文档的信息// fs.chunks这个集合存储的是上传文件的内容。一个chunk相当于一个文档（大文件被拆分成多个有序的chunk）// GridFS中的bucket这个概念指代的是fs.files和fs.chunks的组合// 它的工作原理是：// 在GridFS存储文件是将文件分块存储，文件会按照256KB的大小分割成多个块进行存储// GridFS使用两个集合// （collection）存储文件，一个集合是chunks, 用于存储文件的二进制数据// 一个集合是files，用于存储文件的元数据信息（文件名称、块大小、上传时间等信息）// 从GridFS中读取文件要对文件的各各块进行组装、合并// GridFSBucket 用于打开下载流对象#endregion/// <summary>/// 库 名/// </summary>public abstract string DataBaseName { get; }/// <summary>/// 配置类型/// </summary>public virtual DBConfigTypeEnum DBConfigType { get; set; } = DBConfigTypeEnum.WriteDB;/// <summary>/// 根据 Id 获取内部信息/// </summary>/// <param name="id"></param>/// <returns></returns>public ObjectId GetInternalId(string id){if (!ObjectId.TryParse(id, out ObjectId internalId))internalId = ObjectId.Empty;return internalId;}/// <summary>/// 根据 Id 获取文件 -- 异步/// </summary>/// <param name="id"></param>/// <returns></returns>public async Task<GridFSFileInfo> GetFileById(string id){// 通过系统 Id 筛选出包含 _id 的文件数据var filter = Builders<GridFSFileInfo>.Filter.Eq("_id", GetInternalId(id));return await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).Find(filter).FirstOrDefaultAsync();}/// <summary>/// 根据 Id 获取文件 -- 异步/// </summary>/// <param name="id">文件Id</param>/// <returns></returns>public async Task<GridFSFileInfo> GetFileById(ObjectId id){var filter = Builders<GridFSFileInfo>.Filter.Eq("_id", id);return await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).Find(filter).FirstOrDefaultAsync();}/// <summary>/// 上传文件 -- 异步/// </summary>/// <param name="fileName">文件名称</param>/// <param name="source">流</param>/// <returns></returns>public async Task<ObjectId> UploadFile(string fileName, Stream source){var id = await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).UploadFromStreamAsync(fileName, source);return id;}/// <summary>/// 根据Id 下载文件流可搜索 -- 异步/// </summary>/// <param name="id"></param>/// <returns></returns>public async Task<GridFSDownloadStream<ObjectId>> DownloadFileStreamSeekable(string id){var options = new GridFSDownloadOptions{Seekable = true};return await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).OpenDownloadStreamAsync(GetInternalId(id), options);}/// <summary>/// 根据Id 下载文件流可搜索 -- 异步/// </summary>/// <param name="id"></param>/// <returns></returns>public async Task<GridFSDownloadStream<ObjectId>> DownloadFileStreamSeekable(ObjectId id){var options = new GridFSDownloadOptions{Seekable = true};return await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).OpenDownloadStreamAsync(id, options);}/// <summary>/// 根据 Id 下载文件流 -- 异步/// </summary>/// <param name="id"></param>/// <returns></returns>public async Task<GridFSDownloadStream<ObjectId>> DownloadFileStream(string id){return await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).OpenDownloadStreamAsync(GetInternalId(id));}/// <summary>/// 下载 Id 获取文件流 -- 异步/// </summary>/// <param name="id"></param>/// <returns></returns>public async Task<GridFSDownloadStream<ObjectId>> DownloadFileStream(ObjectId id){return await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).OpenDownloadStreamAsync(id);}/// <summary>/// 根据Id删除文件 -- 异步/// </summary>/// <param name="id"></param>/// <returns></returns>public async Task DeleteFile(string id){await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).DeleteAsync(GetInternalId(id));}/// <summary>/// 根据Id删除文件 -- 异步/// </summary>/// <param name="id"></param>/// <returns></returns>public async Task DeleteFile(ObjectId id){await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).DeleteAsync(id);}/// <summary>/// 根据Id和文件名称移除文件 -- 异步/// </summary>/// <param name="id"></param>/// <param name="newFilename"></param>/// <returns></returns>public async Task RenameFile(string id, string newFilename){await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).RenameAsync(GetInternalId(id), newFilename);}/// <summary>/// 根据Id和文件名称移除文件 --异步/// </summary>/// <param name="id"></param>/// <param name="newFilename"></param>/// <returns></returns>public async Task RenameFile(ObjectId id, string newFilename){await MongoDBClient.GetGridFSBucketInstance(DataBaseName, DBConfigType).RenameAsync(id, newFilename);}}在项目的使用实例
本人比较喜欢封装好再用。所以将上面的帮助类封装成了一个DLL文件，这样在项目中可以直接引用。
项目结构
API层有一个mongoDBConfig.json这个是客户端连接配置文件。
[{"DbName": "PMFiles","ReadConnectionString": "mongodb://192.168.10.200:27017","WriteConnectionString": "mongodb://192.168.10.200:27017"},{"DbName": "Test","ReadConnectionString": "mongodb://192.168.10.200:27017","WriteConnectionString": "mongodb://192.168.10.200:27017"}
]使用很简单，在要引用的类库中直接引用DLL文件就可以。
下面是具体的实例代码：
1.数据访问层
/// <summary>/// MongodbFile处理接口/// </summary>public interface IFileRepository : IMongoFileRepository{}这里创建的接口是空的，没有要扩展的方法，常用的接口都在 IMongoFileRepository 基类接口中定义了.
实现类:
/// <summary>/// Mongodb 文件 数据库 操作类/// </summary>public class FileRepository : MongoFileRepository , IFileRepository{public override string DataBaseName => "PMFiles";}这里创建的实现类也是空的，没有要扩展的方法，常用的接口都在 MongoFileRepository基类中实现了.
注意： 这里重写了DataBaseName这里一定要重写基类的数据库名称。
2.业务层
/// <summary>/// 文件 操作 业务逻辑层接口/// </summary>public interface IFileService : IMongoFileRepository{}实现类
这里主要是调用数据访问层的实例来实现功能。
[AutoInject(typeof(IFileService), InjectType.Scope)]
这里的服务注入用的是自动注入。可以改成手动注册。手动注册时可以删除类上的 AutoInject 标签
/// <summary>/// 文件操作服务/// </summary>[AutoInject(typeof(IFileService), InjectType.Scope)]public class FileService : IFileService{private readonly IFileRepository _srviceFile = RepositoryIocFactory.GetRegisterImp<IFileRepository>();public Task DeleteFile(string id){return _srviceFile.DeleteFile(id);}public Task DeleteFile(ObjectId id){return _srviceFile.DeleteFile(id);}public Task<GridFSDownloadStream<ObjectId>> DownloadFileStream(string id){return _srviceFile.DownloadFileStream(id);}public Task<GridFSDownloadStream<ObjectId>> DownloadFileStream(ObjectId id){return _srviceFile.DownloadFileStream(id);}public Task<GridFSDownloadStream<ObjectId>> DownloadFileStreamSeekable(string id){return _srviceFile.DownloadFileStreamSeekable(id);}public Task<GridFSDownloadStream<ObjectId>> DownloadFileStreamSeekable(ObjectId id){return _srviceFile.DownloadFileStreamSeekable(id);}public Task<GridFSFileInfo> GetFileById(string id){return _srviceFile.GetFileById(id);}public Task<GridFSFileInfo> GetFileById(ObjectId id){return _srviceFile.GetFileById(id);}public ObjectId GetInternalId(string id){return _srviceFile.GetInternalId(id);}public Task RenameFile(string id, string newFilename){return _srviceFile.RenameFile(id, newFilename);}public Task RenameFile(ObjectId id, string newFilename){return _srviceFile.RenameFile(id, newFilename);}public Task<ObjectId> UploadFile(string fileName, Stream source){return _srviceFile.UploadFile(fileName, source);}}1、API层的实现
AIP层主要的接口有 上传 和 根据ID下载文件，以文件流对象返回数据。
/// <summary>/// MongoDB文件上传/// </summary>public class FileUploadController : BaseApiController{private IFileService serviceFile;public FileUploadController(IFileService fileService){serviceFile = fileService;}/// <summary>/// 上传文件/// </summary>/// <returns></returns>[HttpPost, Route("UploadFileAsync")][DisableRequestSizeLimit][DisableFormValueModelBinding]public async Task<AjaxResultPageModel> UploadFileAsync(){var rspModel = new AjaxResultPageModel();var fileIds = new List<string>();//检查ContentTypeif (!MultipartRequestHelper.IsMultipartContentType(Request.ContentType)){rspModel.Warning("内容类型不能为空");}else{var _defaultFormOptions = new FormOptions();var boundary = MultipartRequestHelper.GetBoundary(MediaTypeHeaderValue.Parse(Request.ContentType), _defaultFormOptions.MultipartBoundaryLengthLimit);var reader = new MultipartReader(boundary, Request.Body);var section = await reader.ReadNextSectionAsync();while (section != null){//把Form的栏位內容逐一取出var hasContentDispositionHeader = ContentDispositionHeaderValue.TryParse(section.ContentDisposition, out ContentDispositionHeaderValue contentDisposition);if (hasContentDispositionHeader){//按文件和键值对分类处理if (MultipartRequestHelper.HasFileContentDisposition(contentDisposition)){FileMultipartSection currentFile = section.AsFileSection();//存储文件到Mongovar id = await serviceFile.UploadFile(currentFile.FileName, section.Body);fileIds.Add(id.ToString());}}section = await reader.ReadNextSectionAsync();}rspModel.Success(fileIds);}return rspModel;}/// <summary>/// 下载文件/// </summary>[HttpGet,Route("Download")]public async Task<IActionResult> Download(string id){var fileInfo = await serviceFile.GetFileById(id);if (fileInfo == null){return NotFound();}else{return File(await serviceFile.DownloadFileStream(fileInfo.Id), "application/octet-stream", fileInfo.Filename);}}}前端实现：
前端使用vue组件
<template><div class="home"><el-card class="box-card-top" shadow="never"><el-row :gutter="100"><el-col :span="2"><div class="user-avatar"><p class="user-avatar-text">{{ avatar }}</p></div></el-col><el-col :span="22"><div class="text"><h3>{{ holler }} {{ username }}</h3><p>桂树青春百里疆，鹧鸪啼彻午阴凉. 延平津上峰如削，剑去江空水自长.--剑道·尘心</p><p>活在当下，着眼未来.没有一往无前的觉悟.就不配握紧手中的双刀.空有大志，却没有实际行动.天下万般兵刃.唯有过往，伤人最深.如果真相带来痛苦.谎言只会雪上加霜. --LOL·亚索</p></div></el-col></el-row><!-- <h2>首页界面</h2><div class="hello"> --><!-- <el-input v-model="user" type="text" /> --><!-- <div id="message" v-html="remsg"></div> --><!-- <div id="el-input"><el-input id="chatbox" @keyup.native.enter="handle" type="textarea" :rows="1" placeholder="请输入内容" v-model="msg"></el-input></div><el-button size="small" style="display:inline-block;" icon="el-icon-s-promotion" type="suceess" @click="handle" plain></el-button> --><!-- </div> --></el-card><el-row :gutter="20"><el-col :span="4"><el-card class="box-card-center" shadow="never"><el-upload:action="action":file-list="modeList1":http-request="modeUpload1":multiple="true":before-remove="handleRemove1"><el-button size="small" type="primary">上传</el-button></el-upload><el-button @click="upload1">点击上传文件</el-button><br/><el-button @click="fileUpload">点击上传文件1</el-button></el-card></el-col><el-col :span="4"><el-card class="box-card-center" shadow="never"></el-card></el-col><el-col :span="4"><el-card class="box-card-center" shadow="never"></el-card></el-col></el-row></div></template><script>import axios from 'axios'import config from "../../config/index";import service from "../../api/UploadFiles/index";export default {data() {return {username: null,holler: "欢迎回来 — ",avatar: "",action: "", //上传文件的接口mode1: {},modeList1:[],fd1: new FormData()};},created() {this.username = JSON.parse(sessionStorage.getItem(config.localStorageKey)).userName;this.avatar = this.username.slice(0, 1);},methods: {modeUpload1: function(item) {// console.log(item.file);// this.mode1 = item.file// const isIMG =// item.file.type === 'image/jpg' ||// item.file.type === 'image/jpeg' ||// item.file.type === 'image/png'// const isLt = item.file.size / 1024 / 2000 <= 1// if (!isIMG) {// this.error='文件格式有误\n请上传后缀为jpg\\png的图片'// }// if (!isLt) {// // console.log(file.size)// this.error='上传头像图片大小不能超过500KB!'// }// if(isIMG&&isLt){this.fd1.append('files', item.file); //这里是自己把文件对象获取到，并存储起来//console.log("modeUpload1-> addFile:",item.file);//}},upload1: function() {console.log("upload1-> 11,files.length=",this.fd1.getAll('files').length);if(this.fd1.getAll('files').length===0){//formdata.getAll()返回的是一个file的数组（当然这里是你之前的参数得是文件）this.error='请先上传文件'}else {console.log("upload1-> post");axios.post('https://localhost:5001/adminapi/FileUpload/UploadFileAsync', this.fd1, { //headers: {'Content-Type': 'multipart/form-data'}}).then(response => {console.log("upload1->",response.data);})}},handleRemove1(file, fileList) {let files = this.fd1.getAll('files');this.fd1.delete('files');let len = files.lengthfor(var i=0;i<len;i++){if(files[i].uid!=file.uid){ //uid应该是可以唯一标志文件的，如果不能，就是我，会死this.fd1.append('files',files[i])}}},//上传方法fileUpload(uploader) {//let form = new FormData();//form.append("files", uploader.file);//console.log(this.fd1);//console.log("--------------------------");//console.log(uploader)service.uploadFlie(this.fd1// onUploadProgress: (progressEvent) => {// //这一步是展示上传的进度条，不展示也行，根据自身需求决定// let percent = ((progressEvent.loaded / progressEvent.total) * 100) | 0;// uploader.onProgress({ percent: percent }); //调用uploader的进度回调// },).then((res) => {console.log(res);if (res.success) {this.$message({message: "上传成功",type: "success",});} else {this.$message.error("上传失败,"+res.message);}}).catch((err) => {this.$message.error(err);});},},};/* import * as signalR from "@microsoft/signalr";let hubUrl = "https://localhost:44360/chatHub";//"https://localhost:44367/chatHub";//https://localhost:44318/chatHub; https://localhost:44367/chatHub//.net core 版本中默认不会自动重连，需手动调用 withAutomaticReconnectconst connection = new signalR.HubConnectionBuilder().withAutomaticReconnect().withUrl(hubUrl).build();connection.start().catch(err => alert(err.message));export default {name: "Im",mounted() {var _this = this;console.log('hubUrl:',hubUrl);//实现Show方法 OKconnection.on("Show", function(username, message) {_this.remsg = _this.remsg + "<br>" + username + ":" + message;console.log('Show:',message);});//实现ConnectResponse方法//connection.on("ChatHubReceiveMsg", function(username, message) {// _this.remsg = _this.remsg + "<br>" + username + ":" + message;// console.log('ChatHubReceiveMsg:',message);//}); //实现DisconnectResponse方法//connection.on("DisconnectResponse", function(username, message) {// _this.remsg = _this.remsg + "<br>" + username + ":" + message;// console.log('DisconnectResponse:',message);//});},data() {return {user: "cjh",msg: "",remsg: ""};},methods: {handle: function() {if(this.msg.trim()==""){alert("不能发送空白消息");return;}//调用后端方法 SendMsg 传入参数 OKconnection.invoke("SendMsg", this.user, this.msg);//connection.invoke("PublicSendMsg", this.msg);this.msg = "";}}}; */</script><style lang="less" scoped>.home {margin: 20px;.box-card-top {min-height: 160px;.user-avatar {width: 100px;height: 100px;margin-left: 50px;margin-top: 5px;border-radius: 50%;background-image: linear-gradient(#cdeefa, #b4b4fc);// background-color: #b4b4fc;.user-avatar-text {font-size: 40px;text-align: center;padding-top: 22px;color: #383838;}}.text h3 {margin-top: 20px;margin-bottom: 10px;font-size: 20px;}.text p {font-size: 16px;user-select: none;}}.box-card-center {width: 350px;height: 300px;margin-top: 20px;}}h1,h2 {font-weight: normal;}ul {list-style-type: none;padding: 0;}li {display: inline-block;margin: 0 10px;}a {color: #42b983;}#el-input {display: inline-block;width: 96%;float: left;}#message {overflow-y: auto;text-align: left;border: #42b983 solid 1px;height: 500px;}</style>跨域问题处理。
requestFile.js
注意上图的类型只能是这个类型，只能一个类型，不能多。
//interceptors.js// vue axios配置 发起请求加载loading请求结束关闭loading
// http request 请求拦截器，有token值则配置上token值
import axios from 'axios'
import common from '../utils/common'
// import { API_BASE } from '../config/config';
// axios.defaults.baseURL = API_BASE;
// api base_url，设置前缀不存在
// const BASE_URL="";
const service = axios.create({baseURL: '', timeout: 60000, // 请求超时时间headers: {// Authorization: Authorization,'Content-Type': 'multipart/form-data'}
});
// Content-Type: application/wasmsql-wasm.wasm
// http请求拦截器
service.interceptors.request.use(config => {let token = common.getToken();//console.log('token:', token);if (token) {// bus.$emit('toggleloading', true)//显示loading// Loading.service(options);//如果token存在config.headers['Authorization'] = `Bearer ${token}`;//console.log('token 1:', token);}return config;},error => {Promise.reject(error);}
)// http response 服务器响应拦截器，
// 这里拦截401错误，并重新跳入登页重新获取token
service.interceptors.response.use(response => {if (response.status === 200) {//通讯成功// Toast.clear();// console.log(response);/************** response.data.status === 0 错误* response.data.status === 100 成功* response.data.status === 401 token过期** *************/// response.data.head.errorCode// bus.$emit('toggleloading', false)//隐藏loadingif (response.data.state == 401) {//未授权//如果是token过期，跳转至登录// console.log("401");//common.goLogin();message.error("未授权 请联系管理员！");//store.commit('setToken', '');} else if (response.data.state == 0) {// Message.error(response.data.message);return response.data;} else {// util.goLogin();return response.data;}}},error => {//请求失败// ;const response = error.response;if (response.status === 401) {// Toast.fail(response.data.message);message.error("未授权 请联系管理员！");//util.goLogin();} else if (response.status === 403) {$router.push({name: '403'});} else {// Toast.fail(response.data.message ? response.data.message : '系统错误请联系管理员');// message.error({// message: '无服务，请联系管理员'// });}return Promise.reject(error);}
);export default service;API js
import http from '../../utils/http'export default {// 上传文件uploadFileAsync:(params) => {return http.postMongoDBFile("adminapi/FileUpload/UploadFileAsync",params);},// 下载文件download:(params) => {return http.postMongoDBdownloadFile("adminapi/FileUpload/Download?id="+params)}
};完成。
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