第一部分:/cgzl/p/8478993.html

第二部分:/cgzl/p/8481825.html

第三部分:/cgzl/p/8525541.html

第四部分:/cgzl/p/8536350.html

这部分就讲从angular5的客户端上传图片到 core 2.0的 web api.

这是需要的源码:/s/1Eqc4MRiQDwOHmu0OHyttqA

当前的效果如下:

点击这个超链接后:

好的, 下面开始编写上传相关的代码.

core 2.0 文件上传

按照顺序, 先建立Photo的domain model:

建立Models/Photo.cs:

using ponentModel.DataAnnotations;namespace Tv.Models{public class Photo{public int Id { get; set; }[Required][StringLength(255)]public string FileName { get; set; }}}

然后编辑TvShow.cs:

using System.Collections.Generic;using ponentModel.DataAnnotations;namespace Tv.Models{public class TvShow{public TvShow(){Photoes= new List<Photo>();}public int Id { get; set; }[Required][StringLength(50)]public string Name { get; set; }public int TvNetworkId { get; set; }public TvNetwork TvNetwork { get; set; }public ICollection<Photo> Photoes { get; set; }}}

TvContext.cs:

using Microsoft.EntityFrameworkCore;using Tv.Models;namespace Tv.Database{public class TvContext : DbContext{public TvContext(DbContextOptions<TvContext> options): base(options){}public DbSet<TvNetwork> TvNetworks { get; set; }public DbSet<TvShow> TvShows { get; set; }public DbSet<Photo> Photoes { get; set; }}}

然后添加迁移和更新数据库, 您应该知道怎么做了, 这部分就略了.

添加PhotoViewModel.cs:

namespace Tv.ViewModels{public class PhotoViewModel{public int Id { get; set; }public string FileName { get; set; }}}

不要忘了做一下Mapping映射, 这里我就不写了.

然后建立PhotoesController.cs:

using System;using System.IO;using System.Threading.Tasks;using AutoMapper;using Microsoft.AspNetCore.Hosting;using Microsoft.AspNetCore.Http;using Microsoft.AspNetCore.Mvc;using Tv.Database;using Tv.Models;using Tv.ViewModels;namespace Tv.Controllers{[Route("api/tvshows/{tvShowId}/photoes")]public class PhotoesController : Controller{private readonly IHostingEnvironment host;private readonly ITvRepository tvRepository;private readonly IUnitOfWork unitOfWork;private readonly IMapper mapper;public PhotoesController(IHostingEnvironment host, ITvRepository tvRepository, IUnitOfWork unitOfWork, IMapper mapper){this.host = host;this.tvRepository = tvRepository;this.unitOfWork = unitOfWork;this.mapper = mapper;}[HttpPost]public async Task<IActionResult> Upload(int tvShowId,IFormFilefile){var tvShow = await tvRepository.GetTvShowByIdAsync(tvShowId, includeRelated: false);if (tvShow == null){return NotFound();}var uploadsFolderPath = bine(host.WebRootPath, "Uploads");if (!Directory.Exists(uploadsFolderPath)){Directory.CreateDirectory(uploadsFolderPath);}var fileName = Guid.NewGuid().ToString() + Path.GetExtension(file.FileName);var filePath = bine(uploadsFolderPath, fileName);using (var stream = new FileStream(filePath, FileMode.Create)){await file.CopyToAsync(stream);}var photo = new Photo{FileName = fileName};tvShow.Photoes.Add(photo);await unitOfWork.SaveAsync();var result = mapper.Map<Photo, PhotoViewModel>(photo);return Ok(result);}}}

这里要简单讲一下. core 上传文件的文档在这:/en-us/aspnet/core/mvc/models/file-uploads

首先该controller的路由应该遵循web api的规范, 注意controller 的路由地址.

上传单个文件需要使用IFormFile作为Action的参数. 如果上传的是多个文件, 那么应该使用IFormCollection.

这里我做的是单文件上传, 所以使用IFormFile.

随后使用注入的IHostingEnvironment获得wwwroot目录, 我想要把文件上传到wwwroot/uploads下, 判断该目录是否存在, 如果不存在则创建该目录.

为了防黑, 把文件名改成Guid, 后缀名不变.

然后使用FileStream创建该文件.

后边的内容就是把文件名保存到数据库了.

接下来, 使用Postman来测试这个api.

打开postman, 按照图示输入:

注意这里的参数的key为file, 这个名字要与action的参数名一致:

send:

很好, 测试通过.

下面为Action添加一些验证:

这就是一些常规的验证, 没有什么特别的, 就不累述了.

针对这些东西, 您可以使用配置类, 并把相关的值放在appSettings.json里面. 这部分您自己学一下吧 /en-us/aspnet/core/fundamentals/configuration/?tabs=basicconfiguration.

下面是客户端

Angular 5 文件上传

先做ui, tv-show-ponent.html:

<form><h2>基本信息</h2><div class="form-group row"><label for="name" class="col-sm-2 col-form-label">名称</label><div class="col-sm-10"><input type="text" readonly class="form-control-plaintext" id="name" value="{{model.name}}"></div></div><h2>电视剧照片</h2><div class="form-group row"><label for="file" class="col-sm-2 col-form-label">照片</label><input type="file" name="file" id="file" class="form-control"#fileInput(change)="upload()"></div></form>

注意这里使用了template reference.

然后创建一个photo.service:

import { Injectable } from '@angular/core';import { HttpHeaders, HttpClient } from '@angular/common/http';@Injectable()export class PhotoService {constructor(private http: HttpClient) { }upload(tvShowId: number, photo) {const formData = newFormData();formData.append('file', photo);return this.http.post(`/api/tvshows/${tvShowId}/photoes`, formData);}}

其中post的参数类型是FormData, 它是js原生对象. formData里面文件的key要和后台Action方法的参数名一样.

最后改一下tv-show-ponent.ts:

import { Component, OnInit, ElementRef, ViewChild } from '@angular/core';import { TvShowService } from '../../services/tv-show.service';import { Router, ActivatedRoute, ParamMap } from '@angular/router';import { TvShow } from '../../models/tv-show';import { Subscription } from 'rxjs/Subscription';import { ToastrService } from 'ngx-toastr';import { PhotoService } from '../../services/photo.service';@Component({selector: 'app-tv-show-detail',templateUrl: './tv-show-ponent.html',styleUrls: ['./tv-show-ponent.css']})export class TvShowDetailComponent implements OnInit {tvShowId: number;@ViewChild('fileInput') fileInput: ElementRef;model: TvShow = new TvShow();busy: Subscription;constructor(private tvShowService: TvShowService,private router: Router,private route: ActivatedRoute,private toastr: ToastrService,private photoService: PhotoService) { }ngOnInit() {this.route.paramMap.switchMap((params: ParamMap) => {this.tvShowId = +params.get('id');return this.tvShowService.getById(this.tvShowId);}).subscribe(item => {this.model = item;});}upload() {const ele= this.fileInput.nativeElement;this.photoService.upload(this.tvShowId, ele.files[0]).subscribe(x =>{console.log(x);});}}

如果上传成功, 那么回来先只做打印到log. 试一下:

上传成功. 文件即出现在wwwroot下, 文件名也保存到了数据库.

回显照片:

首先修改Photo.cs:

using ponentModel.DataAnnotations;namespace Tv.Models{public class Photo{public int Id { get; set; }[Required][StringLength(255)]public string FileName { get; set; }public int TvShowId { get; set; }public TvShow TvShow { get; set; }}}

不要忘记迁移数据库.

然后创建Repository, 并注册:

using System.Collections.Generic;using System.Threading.Tasks;using Tv.Models;namespace Tv.Database{public interface IPhotoRepository{Task<List<Photo>> GetPhotoesByTvShowIdAsync(int tvShowId);}}

using System.Collections.Generic;using System.Linq;using System.Threading.Tasks;using Microsoft.EntityFrameworkCore;using Tv.Models;namespace Tv.Database{public class PhotoRepository : IPhotoRepository{private readonly TvContext context;public PhotoRepository(TvContext context){this.context = context;}public async Task<List<Photo>> GetPhotoesByTvShowIdAsync(int tvShowId){var photoes = await context.Photoes.Where(x => x.TvShowId == tvShowId).ToListAsync();return photoes;}}}

最后修改PhotoesController:

using System;using System.IO;using System.Linq;using System.Threading.Tasks;using AutoMapper;using Microsoft.AspNetCore.Hosting;using Microsoft.AspNetCore.Http;using Microsoft.AspNetCore.Mvc;using Tv.Database;using Tv.Models;using Tv.ViewModels;namespace Tv.Controllers{[Route("api/tvshows/{tvShowId}/photoes")]public class PhotoesController : Controller{private readonly IHostingEnvironment host;private readonly ITvRepository tvRepository;private readonly IUnitOfWork unitOfWork;private readonly IMapper mapper;private readonly IPhotoRepository photoRepository;public PhotoesController(IHostingEnvironment host, ITvRepository tvRepository, IUnitOfWork unitOfWork, IMapper mapper, IPhotoRepository photoRepository){this.host = host;this.tvRepository = tvRepository;this.unitOfWork = unitOfWork;this.mapper = mapper;this.photoRepository = photoRepository;}[HttpPost]public async Task<IActionResult> Upload(int tvShowId, IFormFile file){var tvShow = await tvRepository.GetTvShowByIdAsync(tvShowId, includeRelated: false);if (tvShow == null){return NotFound();}if (file == null){return BadRequest("File is null");}if (file.Length == 0){return BadRequest("File is Empty");}if (file.Length > 10 * 1024 * 1024){return BadRequest("文件大小不能超过10M");}var acceptedTypes = new[] { ".jpg", ".png", ".jpeg" };if (acceptedTypes.All(t => t != Path.GetExtension(file.FileName).ToLower())){return BadRequest("文件类型不对");}var uploadsFolderPath = bine(host.WebRootPath, "Uploads");if (!Directory.Exists(uploadsFolderPath)){Directory.CreateDirectory(uploadsFolderPath);}var fileName = Guid.NewGuid().ToString() + Path.GetExtension(file.FileName);var filePath = bine(uploadsFolderPath, fileName);using (var stream = new FileStream(filePath, FileMode.Create)){await file.CopyToAsync(stream);}var photo = new Photo{FileName = fileName};tvShow.Photoes.Add(photo);await unitOfWork.SaveAsync();var result = mapper.Map<Photo, PhotoViewModel>(photo);return Ok(result);}[HttpGet]public async Task<IActionResult> GetPhotoesByTvShowId(int tvShowId){var photoes = await photoRepository.GetPhotoesByTvShowIdAsync(tvShowId);returnOk(photoes);}}}

然后修改angular部分:

添加Photo到model:

export class Photo {id: number;tvShowId: number;fileName: string;}

修改photo service:

import { Injectable } from '@angular/core';import { HttpHeaders, HttpClient } from '@angular/common/http';import { Observable } from 'rxjs/Observable';import { Photo } from '../models/photo';@Injectable()export class PhotoService {constructor(private http: HttpClient) { }upload(tvShowId: number, photo): Observable<Photo> {const formData = new FormData();formData.append('file', photo);return this.http.post<Photo>(`/api/tvshows/${tvShowId}/photoes`, formData);}getPhotoes(tvShowId: number): Observable<Photo[]> {return this.http.get<Photo[]>(`/api/tvshows/${tvShowId}/photoes`);}}

tv-show-ponent.html:

<form><h2>基本信息</h2><div class="form-group row"><label for="name" class="col-sm-2 col-form-label">名称</label><div class="col-sm-10"><input type="text" readonly class="form-control-plaintext" id="name" value="{{model.name}}"></div></div><h2>电视剧照片</h2><div class="form-group row"><label for="file" class="col-sm-2 col-form-label">照片</label><input type="file" name="file" id="file" class="form-control" #fileInput (change)="upload()"></div><div><img [src]="'http://localhost:5000/Uploads/' + p.fileName" [alt]="p.fileName" *ngFor="let p of photoes" class="m-1" width="200"height="200" /></div></form>

tv-show-ponent.ts:

import { Component, OnInit, ElementRef, ViewChild } from '@angular/core';import { TvShowService } from '../../services/tv-show.service';import { Router, ActivatedRoute, ParamMap } from '@angular/router';import { TvShow } from '../../models/tv-show';import { Subscription } from 'rxjs/Subscription';import { ToastrService } from 'ngx-toastr';import { PhotoService } from '../../services/photo.service';import { Photo } from '../../models/photo';import { Observable } from 'rxjs/Observable';import 'rxjs/add/observable/forkJoin';@Component({selector: 'app-tv-show-detail',templateUrl: './tv-show-ponent.html',styleUrls: ['./tv-show-ponent.css']})export class TvShowDetailComponent implements OnInit {tvShowId: number;@ViewChild('fileInput') fileInput: ElementRef;model: TvShow = new TvShow();busy: Subscription;photoes: Photo[] = [];constructor(private tvShowService: TvShowService,private router: Router,private route: ActivatedRoute,private toastr: ToastrService,private photoService: PhotoService) { }ngOnInit() {this.route.paramMap.switchMap((params: ParamMap) => {this.tvShowId = +params.get('id');return Observable.forkJoin<TvShow, Photo[]>(this.tvShowService.getById(this.tvShowId),this.photoService.getPhotoes(this.tvShowId));}).subscribe(([tvShow, photoes]) => {this.model = tvShow;this.photoes = photoes;});}upload() {const ele = this.fileInput.nativeElement;this.photoService.upload(this.tvShowId, ele.files[0]).subscribe(photo => {this.photoes.push(photo);});}}

这部分比较简单, 注意同时发送多个请求可以使用forkJoin.

看看效果:

如果照片没有显示出来, 可能是 core没有启用静态文件到支持, 在Startup.cs添加这句话即可:

using System;using System.Collections.Generic;using System.Linq;using System.Threading.Tasks;using AutoMapper;using Microsoft.AspNetCore.Builder;using Microsoft.AspNetCore.Hosting;using Microsoft.EntityFrameworkCore;using Microsoft.Extensions.Configuration;using Microsoft.Extensions.DependencyInjection;using Microsoft.Extensions.Logging;using Tv.Database;namespace Tv{public class Startup{public Startup(IConfiguration configuration){Configuration = configuration;}public IConfiguration Configuration { get; }// This method gets called by the runtime. Use this method to add services to the container.public void ConfigureServices(IServiceCollection services){services.AddAutoMapper();// services.AddDbContext<TvContext>(opt => opt.UseSqlServer(Configuration["ConnectionStrings:Default"]));services.AddDbContext<TvContext>(opt => opt.UseSqlServer(Configuration.GetConnectionString("Default")));services.AddScoped<ITvRepository, TvRepository>();services.AddScoped<IPhotoRepository, PhotoRepository>();services.AddScoped<IUnitOfWork, UnitOfWork>();services.AddMvc();}// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.public void Configure(IApplicationBuilder app, IHostingEnvironment env){if (env.IsDevelopment()){app.UseDeveloperExceptionPage();}app.UseStaticFiles();app.UseMvc();}}}

很好. 即使是刚添加完到照片也会即时显示出来.

上传进度显示.

首先创建一个修改photo service:

根据官方文档, 如果想要上传文件时显示进度, 那么应该使用HttpRequest, 并设置属性reportProgress为true:

import { Injectable } from '@angular/core';import { HttpHeaders, HttpClient, HttpRequest, HttpEvent, HttpEventType, HttpErrorResponse } from '@angular/common/http';import { Observable } from 'rxjs/Observable';import { Photo } from '../models/photo';@Injectable()export class PhotoService {constructor(private http: HttpClient) { }upload(tvShowId: number, photo: File) {const formData = new FormData();formData.append('file', photo);// return this.http.post<Photo>(`/api/tvshows/${tvShowId}/photoes`, formData);const req = new HttpRequest('POST', `/api/tvshows/${tvShowId}/photoes`, formData, {reportProgress: true});return this.http.request<Photo>(req);}getPhotoes(tvShowId: number): Observable<Photo[]> {return this.http.get<Photo[]>(`/api/tvshows/${tvShowId}/photoes`);}}

回到 tv-show-ponent.ts:

import { Component, OnInit, ElementRef, ViewChild } from '@angular/core';import { TvShowService } from '../../services/tv-show.service';import { Router, ActivatedRoute, ParamMap } from '@angular/router';import { TvShow } from '../../models/tv-show';import { Subscription } from 'rxjs/Subscription';import { ToastrService } from 'ngx-toastr';import { PhotoService } from '../../services/photo.service';import { Photo } from '../../models/photo';import { Observable } from 'rxjs/Observable';import 'rxjs/add/observable/forkJoin';import { HttpEvent, HttpEventType } from '@angular/common/http';import { HttpResponse } from 'selenium-webdriver/http';@Component({selector: 'app-tv-show-detail',templateUrl: './tv-show-ponent.html',styleUrls: ['./tv-show-ponent.css']})export class TvShowDetailComponent implements OnInit {tvShowId: number;@ViewChild('fileInput') fileInput: ElementRef;model: TvShow = new TvShow();busy: Subscription;photoes: Photo[] = [];constructor(private tvShowService: TvShowService,private router: Router,private route: ActivatedRoute,private toastr: ToastrService,private photoService: PhotoService) { }ngOnInit() {this.route.paramMap.switchMap((params: ParamMap) => {this.tvShowId = +params.get('id');return Observable.forkJoin<TvShow, Photo[]>(this.tvShowService.getById(this.tvShowId),this.photoService.getPhotoes(this.tvShowId));}).subscribe(([tvShow, photoes]) => {this.model = tvShow;this.photoes = photoes;});}upload() {const ele = this.fileInput.nativeElement;const file = ele.files[0];this.photoService.upload(this.tvShowId, file).subscribe((event: HttpEvent<any>)=> {switch (event.type) {case HttpEventType.Sent:console.log(`开始上传 "${file.name}", 大小是: ${file.size}.`);break;case HttpEventType.UploadProgress:const percentDone= Math.round(100 * event.loaded / event.total);console.log(`文件 "${file.name}" 的上传进度是 ${percentDone}%.`);break;case HttpEventType.Response:console.log(`文件 "${file.name}" 上传成功!`);this.toastr.success(`文件 "${file.name}" 上传成功!`);this.photoes.push(<Photo>(event.body));break;default:console.log(`文件 "${file.name}" 的事件类型: ${event.type}.`);break;}});}}

这样, 上传文件时, 每个进度都会返回一个event, 我暂时就先把它打印到控制台.

看一下效果:

好的, 文件太小, 本地到速度又太快, 进度直接100%了.

那我改一下Chrome的设置, 打开Developer Tools的Network 选项, 然后点击这里:

然后添加:

添加一个非常慢的网速限制:

最后选取这个限制:

实际上, 选择Slow 3G就很慢了.

这时, 再上传一次试试效果:

很好, 没问题.

接下来就是UI显示进度条的问题了, 很简单:

打开html:

<form><h2>基本信息</h2><div class="form-group row"><label for="name" class="col-sm-2 col-form-label">名称</label><div class="col-sm-10"><input type="text" readonly class="form-control-plaintext" id="name" value="{{model.name}}"></div></div><h2>电视剧照片</h2><div class="form-group row"><label for="file" class="col-sm-2 col-form-label">照片</label><input type="file" name="file" id="file" class="form-control" #fileInput (change)="upload()"></div><div class="progress" *ngIf="progress"><div class="progress-bar progress-bar-striped progress-bar-animated" role="progressbar" aria-valuenow="0" aria-valuemin="0"aria-valuemax="100" [style.width]="progress"></div></div><div><img [src]="'http://localhost:5000/Uploads/' + p.fileName" [alt]="p.fileName" *ngFor="let p of photoes" class="m-1" width="200"height="200" /></div></form>

打开tv-show-ponent.ts:

import { Component, OnInit, ElementRef, ViewChild } from '@angular/core';import { TvShowService } from '../../services/tv-show.service';import { Router, ActivatedRoute, ParamMap } from '@angular/router';import { TvShow } from '../../models/tv-show';import { Subscription } from 'rxjs/Subscription';import { ToastrService } from 'ngx-toastr';import { PhotoService } from '../../services/photo.service';import { Photo } from '../../models/photo';import { Observable } from 'rxjs/Observable';import 'rxjs/add/observable/forkJoin';import { HttpEvent, HttpEventType } from '@angular/common/http';import { HttpResponse } from 'selenium-webdriver/http';@Component({selector: 'app-tv-show-detail',templateUrl: './tv-show-ponent.html',styleUrls: ['./tv-show-ponent.css']})export class TvShowDetailComponent implements OnInit {tvShowId: number;@ViewChild('fileInput') fileInput: ElementRef;model: TvShow = new TvShow();busy: Subscription;photoes: Photo[] = [];progress: string;constructor(private tvShowService: TvShowService,private router: Router,private route: ActivatedRoute,private toastr: ToastrService,private photoService: PhotoService) { }ngOnInit() {this.route.paramMap.switchMap((params: ParamMap) => {this.tvShowId = +params.get('id');return Observable.forkJoin<TvShow, Photo[]>(this.tvShowService.getById(this.tvShowId),this.photoService.getPhotoes(this.tvShowId));}).subscribe(([tvShow, photoes]) => {this.model = tvShow;this.photoes = photoes;});}upload() {const ele = this.fileInput.nativeElement;const file = ele.files[0];

ele.value = ''; // 上传图片后,把input的值清空.this.photoService.upload(this.tvShowId, file).subscribe((event: HttpEvent<any>) => {switch (event.type) {case HttpEventType.Sent:console.log(`开始上传 "${file.name}", 大小是: ${file.size}.`);break;case HttpEventType.UploadProgress:const percentDone = Math.round(100 * event.loaded / event.total);this.progress = `${percentDone}%`;console.log(`文件 "${file.name}" 的上传进度是 ${percentDone}%.`);break;case HttpEventType.Response:console.log(`文件 "${file.name}" 上传成功!`);this.toastr.success(`文件 "${file.name}" 上传成功!`);this.photoes.push(<Photo>(event.body));this.progress = null;break;default:console.log(`文件 "${file.name}" 的事件类型: ${event.type}.`);break;}});}}

试试效果:

OK, 没问题!

今天就写到这吧.