asp.net zero 8.2 学习-12- abp 文件上传、获取、删除

约定不等于承诺〃 2021-07-26 19:47 826阅读 0赞

## 1. 页面布局 ##

我们先按照第二讲的方法 [创建一个页面][Link 1] 创建出一个空页面。  
先创建一个Controller,比如MetronicController，再创建一个Action方法：UploadFile，再给UploadFile方法添加一个视图，复制空页面的内容到该视图UploadFile.cshtml  
接着写上传文件的form表单  
整体视图如下：

@using EDU.SIS.Web.Areas.app.Startup
    @using EDU.SIS.Authorization
    
    @{
        ViewBag.CurrentPageName = appPageNames.Common.MetronicUploadFile;
    }
    
    
    
    <div class="kt-content kt-grid__item kt-grid__item--fluid kt-grid kt-grid--hor">
    
        <div class="kt-subheader kt-grid__item">
            <div class="@(await GetContainerClass())">
    
                
                <div class="kt-subheader__main">
                    <h3 class="kt-subheader__title">
                        <span>文件上传</span>
                    </h3>
                </div>
                
            </div>
        </div>
    
        <div class="@(await GetContainerClass()) kt-grid__item kt-grid__item--fluid">
            <div class="kt-portlet kt-portlet--mobile">
    
                <div class="kt-portlet__body">
    
                    <form class="kt-form kt-form--center kt-form--label-right" id="kt_form_upload">
                        <div class="kt-portlet__body">
                            <div class="form-group kt-form__group row">
                                <label class="col-form-label col-lg-3 col-sm-12">附件上传</label>
                                <div class="col-lg-4 col-md-9 col-sm-12">
                                    <div class="input-group">
                                        <input id="txt_uploadFileId" type="hidden" />
                                        <input id="txt_fileName" type="text" class="form-control kt-input" name="fileName" readonly autocomplete="off" placeholder="附件名称">
                                        <div class="input-group-append">
                                            <span class="btn btn-primary fileinput-button">
                                                <i class="glyphicon glyphicon-plus"></i>
                                                <span>选择文件</span>
                                                <input id="fileupload" type="file" name="files" accept="image/*">
                                            </span>
                                        </div>
                                    </div>
                                    <span class="kt-form__help">上传进度</span>
                                    <div id="progress" class="progress">
                                        <div class="progress-bar progress-bar-success"></div>
                                    </div>
                                </div>
                            </div>
    
                            <div class="form-group kt-form__group row">
                                <label class="col-form-label col-lg-3 col-sm-12">获取附件</label>
                                <div class="col-lg-4 col-md-9 col-sm-12">
                                    <div class="input-group">
                                        <input id="txt_enclosureId" type="text" class="form-control kt-input" name="enclosureId" required autocomplete="off" placeholder="请输入附件ID">
                                        <div class="input-group-append">
                                            <button id="btn_get_enclosure" class="btn btn-primary" type="button">附件详情</button>
                                        </div>
                                    </div>
                                    <span class="kt-form__help">附件详情将在控制台输出</span>
                                </div>
                            </div>
    
                            <div class="form-group kt-form__group row">
                                <label class="col-form-label col-lg-3 col-sm-12">删除附件</label>
                                <div class="col-lg-4 col-md-9 col-sm-12">
                                    <div class="input-group">
                                        <input id="txt_fileToDeleteId" type="text" class="form-control kt-input" name="fileToDeleteId" required autocomplete="off" placeholder="请输入附件ID">
                                        <div class="input-group-append">
                                            <button id="btn_delete_file" class="btn btn-primary" type="button">附件详情</button>
                                        </div>
                                    </div>
                                    <span class="kt-form__help">删除附件</span>
                                </div>
                            </div>
    
                        </div>
                    </form>
    
                </div>
            </div>
        </div>
    </div>
    
    @section Scripts{
        <script src="~/view-resources/Areas/app/Views/Metronic/Index.js"></script>
        <script> </script>
    }

## 2. 前端js ##

在页面的Index.js文件种编写javascript脚本，这里使用了一个前端上传文件的jquery插件：jquery.fileupload.js，这个插件是在视图布局文件中已经绑定了压缩打包版app-layout-libs，不用再单独引用。  
Index.js源码如下：

## 3. 后端代码 ##

后端与上传文件相关的代码包括领域实体层的BinaryObject，这里对其扩展，添加了文件类型、大小等相关字段：

using System;
    using System.ComponentModel.DataAnnotations;
    using System.ComponentModel.DataAnnotations.Schema;
    using Abp;
    using Abp.Domain.Entities;
    
    namespace EDU.SIS.Storage
    {
        /// <summary>
        /// 附件实体
        /// </summary>
        [Table("AppBinaryObjects")]
        public class BinaryObject : Entity<Guid>, IMayHaveTenant
        {
            /// <summary>
            /// 租户ID
            /// </summary>
            public virtual int? TenantId { get; set; }
    
            /// <summary>
            /// 文件类型【拓展字段】
            /// </summary>
            public virtual string ContentType { get; set; }
    
            /// <summary>
            /// 文件名称【拓展字段】
            /// </summary>
            public virtual string FileName { get; set; }
    
            /// <summary>
            /// 文件大小【拓展字段】
            /// </summary>
            public virtual long FileSize { get; set; }
    
            /// <summary>
            /// 二进制数据
            /// </summary>
            [Required]
            public virtual byte[] Bytes { get; set; }
    
            public BinaryObject()
            {
                Id = SequentialGuidGenerator.Instance.Create();
            }
    
            public BinaryObject(int? tenantId, byte[] bytes)
                : this()
            {
                TenantId = tenantId;
                Bytes = bytes;
            }
        }
    }

还包括IBinaryObjectManager、DbBinaryObjectManager实现文件上传的领域服务，未修改。  
接下来就是在Controller中编写上传文件处理、获取文件详情等方法：

/// <summary>
            /// 上传文件界面
            /// </summary>
            /// <returns></returns>
            [HttpGet]
            public IActionResult UploadFile()
            {
                return View();
            }
    
            /// <summary>
            /// 文件上传
            /// </summary>
            /// <returns></returns>
            [HttpPost]
            public async Task<JsonResult> UploadFilePost()
            {
                try
                {
                    //获取上传对象
                    var file = Request.Form.Files.First();
    
                    //判断是否选择文件
                    if (file == null)
                    {
                        throw new UserFriendlyException(L("File_Empty_Error"));
                    }
    
                    //判断文件大小（单位：字节）
                    if (file.Length > 10485760) //10MB = 1024 * 1024 *10
                    {
                        throw new UserFriendlyException(L("File_SizeLimit_Error"));
                    }
    
                    //将文件流转为二进制数据
                    byte[] fileBytes;
                    using (var stream = file.OpenReadStream())
                    {
                        fileBytes = stream.GetAllBytes();
                    }
    
                    
    
                    //创建附件对象
                    var fileObject = new BinaryObject()
                    {
                        TenantId = AbpSession.TenantId,
                        Bytes = fileBytes,
                        ContentType = file.ContentType,
                        FileName = file.FileName,
                        FileSize = file.Length
                    };
    
                    //上传文件存储路径
                    string destPath = _webHostEnvironment.WebRootPath + "\\uploads\\";
                    if (!Directory.Exists(destPath))
                    {
                        Directory.CreateDirectory(destPath);
                    }
                    //生成随机文件名
                    var fileExtension = Path.GetExtension(file.FileName).ToLowerInvariant();
                    string fileName = fileObject.Id + fileExtension;//需要查找没有扩展名的文件??
                    string filePath = Path.Combine(destPath, fileName);
                    //存放文件到本地
                    using (FileStream fs = System.IO.File.Create(filePath))
                    {
                        file.CopyTo(fs);
                        fs.Flush();
                    }
    
                    //附件对象保存到数据库
                    await _binaryObjectManager.SaveAsync(fileObject);
    
                    //返回给前端上传结果
                    return Json(new AjaxResponse(new
                    {
                        id = fileObject.Id,
                        contentType = file.ContentType,
                        defaultFileName = file.FileName
                    }));
    
                }
                catch (UserFriendlyException ex)
                {
                    return Json(new AjaxResponse(new ErrorInfo(ex.Message)));
                }
                catch(Exception ex)
                {
                    return Json(new AjaxResponse(new ErrorInfo(ex.Message)));
                }
            }
    
            /// <summary>
            /// 删除文件
            /// </summary>
            /// <param name="id"></param>
            /// <returns></returns>
            public async Task<IActionResult> DeleteFile(string id)
            {
                try
                {
                    var fileId = new Guid(id);
                    var fileToDelete = await _binaryObjectManager.GetOrNullAsync(fileId);
                    if (fileToDelete != null)
                    {
                        //string filePath = _webHostEnvironment.WebRootPath + "\\uploads\\"+ fileToDelete.FileName;
                        await _binaryObjectManager.DeleteAsync(fileId);
                        return Json(new AjaxResponse(true));
                    }
                    else
                    {
                        return Json(new AjaxResponse(new ErrorInfo
                        {
                            Message = "文件不存在或删除文件失败"
                        }));
                    }
                }
                catch (Exception)
                {
                    return Json(new AjaxResponse(new ErrorInfo
                    {
                        Message = "文件ID无效"
                    }));
                }
                
            }
    
            /// <summary>
            /// 获取附件
            /// </summary>
            /// <param name="id">附件ID</param>
            /// <param name="contentType">附件类型</param>
            /// <returns></returns>
            public async Task<IActionResult> GetFile(Guid id, string contentType)
            {
                var fileObject = await _binaryObjectManager.GetOrNullAsync(id);
                if (fileObject == null)
                {
                    return StatusCode((int)HttpStatusCode.NotFound);
                }
    
                return File(fileObject.Bytes, contentType);
            }
    
            /// <summary>
            /// 获取附件详情
            /// </summary>
            /// <param name="id">附件ID</param>
            /// <returns></returns>
            [HttpGet]
            public async Task<IActionResult> GetFileDetail(Guid id)
            {
                var fileObject = await _binaryObjectManager.GetOrNullAsync(id);
                if (fileObject == null)
                {
                    return StatusCode((int)HttpStatusCode.NotFound);
                }
    
                return Json(new AjaxResponse(new
                {
                    id = fileObject.Id,
                    fileName = fileObject.FileName,
                    contentType = fileObject.ContentType,
                    fileSize = fileObject.FileSize,
                    fileSizeFormat = FormatFileSize(fileObject.FileSize),
                    bytes = fileObject.Bytes,
                    tenantId = fileObject.TenantId,
                    downloadUrl = string.Format("{0}app/Metronic/GetFile?id={1}&contentType={2}", _appConfiguration["App:WebSiteRootAddress"], fileObject.Id, fileObject.ContentType)
                }));
            }

这里abp官方上传的文件都是存放在数据库中，对于存放大的文件很不科学。可以修改代码存放到本地，也可以参考Magicodes.Storage这个开源库，实现本地存储或者云端OSS存储。

## 4. 系统文件上传大小限制 ##

系统文件上传大小限制可以在代码中实现，也可以通过配置实现，但是最大不会超过配置内规定的大小，在MVC项目的Web.config中修改最大上传大小限制

...
        <security>
          <requestFiltering>
            
            <requestLimits maxAllowedContentLength="524288000" />
          </requestFiltering>
        </security>
      </system.webServer>
      <system.web>
        
        <httpRuntime maxRequestLength="512000" executionTimeout="120" />
      </system.web>

## 5. 测试 ##

![format_png][]

[Link 1]: https://www.cnblogs.com/AlexanderZhao/p/12353245.html
[format_png]: /images/20210726/c57d3c04c03943eea259c4ab24e7df2d.png