角度文件上传

cor*_*114 127 typescript angular

我是Angular的初学者,我想知道如何创建Angular 5 文件上传部分,我试着找到任何教程或文档,但我什么都没看到.对此有何看法?我正在尝试ng4文件,但它不适用于Angular 5

Gre*_*nko 300

以下是将文件上传到api的工作示例:

第1步:HTML模板(file-upload.component.html)

定义类型的简单输入标记file.为(change)-event 添加一个函数来处理选择文件.

<div class="form-group">
    <label for="file">Choose File</label>
    <input type="file"
           id="file"
           (change)="handleFileInput($event.target.files)">
</div>
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第2步:在TypeScript中上传处理(file-upload.component.ts)

为所选文件定义默认变量.

fileToUpload: File = null;
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创建在(change)文件输入标记的事件中使用的函数:

handleFileInput(files: FileList) {
    this.fileToUpload = files.item(0);
}
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如果要处理多文件选择,则可以遍历此文件数组.

现在通过调用file-upload.service创建文件上传功能:

uploadFileToActivity() {
    this.fileUploadService.postFile(this.fileToUpload).subscribe(data => {
      // do something, if upload success
      }, error => {
        console.log(error);
      });
  }
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第3步:文件上传服务(file-upload.service.ts)

通过POST方法上传文件,您应该使用FormData,因为您可以将文件添加到http请求.

postFile(fileToUpload: File): Observable<boolean> {
    const endpoint = 'your-destination-url';
    const formData: FormData = new FormData();
    formData.append('fileKey', fileToUpload, fileToUpload.name);
    return this.httpClient
      .post(endpoint, formData, { headers: yourHeadersConfig })
      .map(() => { return true; })
      .catch((e) => this.handleError(e));
}
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所以,这是一个非常简单的工作示例,我在工作中每天都使用它.

  • 这在Safari或Edge上不起作用 (4认同)
  • @Katie你启用了polyfills吗? (4认同)
  • 我如何在您的示例中设置标题?我如何定义“yourHeadersConfig”? (3认同)
  • @GregorDoroschenko我试图使用一个模型以及有关该文件的其他信息,我必须这样做才能使它工作:`const invFormData:FormData = new FormData(); invFormData.append('invoiceAttachment',invoiceAttachment,invoiceAttachment.name); invFormData.append('invoiceInfo',JSON.stringify(invoiceInfo));`控制器有两个相应的参数,但我不得不解析控制器中的JSON.我的Core 2控制器不会自动拾取参数中的模型.我的原始设计是一个带有文件属性的模型,但我无法让它工作 (2认同)
  • 使用 angular 5,这是行不通的。表单数据为空 (2认同)
  • ```$event.target.files``` 有什么用? (2认同)

Hie*_*yen 11

这样,我将上传文件实现为项目中的Web API。

我与谁分享关注。

const formData: FormData = new FormData();
formData.append('Image', image, image.name);
formData.append('ComponentId', componentId);
return this.http.post('/api/dashboard/UploadImage', formData);
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一步步

ASP.NET Web API

const formData: FormData = new FormData();
formData.append('Image', image, image.name);
formData.append('ComponentId', componentId);
return this.http.post('/api/dashboard/UploadImage', formData);
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HTML表格

[HttpPost]
[Route("api/dashboard/UploadImage")]
public HttpResponseMessage UploadImage() 
{
    string imageName = null;
    var httpRequest = HttpContext.Current.Request;
    //Upload Image
    var postedFile = httpRequest.Files["Image"];
    //Create custom filename
    if (postedFile != null)
    {
        imageName = new String(Path.GetFileNameWithoutExtension(postedFile.FileName).Take(10).ToArray()).Replace(" ", "-");
        imageName = imageName + DateTime.Now.ToString("yymmssfff") + Path.GetExtension(postedFile.FileName);
        var filePath = HttpContext.Current.Server.MapPath("~/Images/" + imageName);
        postedFile.SaveAs(filePath);
    }
}
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使用API​​的TS文件

OnSubmit(Image) {
    this.dashboardService.uploadImage(this.componentId, this.fileToUpload).subscribe(
      data => {
        console.log('done');
        Image.value = null;
        this.imageUrl = "/assets/img/logo.png";
      }
    );
  }
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服务TS

uploadImage(componentId, image) {
        const formData: FormData = new FormData();
        formData.append('Image', image, image.name);
        formData.append('ComponentId', componentId);
        return this.http.post('/api/dashboard/UploadImage', formData);
    }
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Sha*_*med 11

  1. HTML

    <div class="form-group">
      <label for="file">Choose File</label><br /> <input type="file" id="file" (change)="uploadFiles($event.target.files)">
    </div>

    <button type="button" (click)="RequestUpload()">Ok</button>

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  1. .ts 文件
public formData = new FormData();
ReqJson: any = {};

uploadFiles( file ) {
        console.log( 'file', file )
        for ( let i = 0; i < file.length; i++ ) {
            this.formData.append( "file", file[i], file[i]['name'] );
        }
    }

RequestUpload() {
        this.ReqJson["patientId"] = "12"
        this.ReqJson["requesterName"] = "test1"
        this.ReqJson["requestDate"] = "1/1/2019"
        this.ReqJson["location"] = "INDIA"
        this.formData.append( 'Info', JSON.stringify( this.ReqJson ) )
            this.http.post( '/Request', this.formData )
                .subscribe(( ) => {                 
                });     
    }
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  1. 后端Spring(java文件)

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;

@Controller
public class Request {
    private static String UPLOADED_FOLDER = "c://temp//";

    @PostMapping("/Request")
    @ResponseBody
    public String uploadFile(@RequestParam("file") MultipartFile file, @RequestParam("Info") String Info) {
        System.out.println("Json is" + Info);
        if (file.isEmpty()) {
            return "No file attached";
        }
        try {
            // Get the file and save it somewhere
            byte[] bytes = file.getBytes();
            Path path = Paths.get(UPLOADED_FOLDER + file.getOriginalFilename());
            Files.write(path, bytes);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return "Succuss";
    }
}
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我们必须在 C 盘创建一个文件夹“temp”,然后这段代码将在控制台打印 Json 并将上传的文件保存在创建的文件夹中


Ahm*_*ies 10

首先,您需要在 Angular 项目中设置 HttpClient。

打开src/app/app.module.ts文件,导入HttpClientModule并添加到模块的imports数组中,如下:

import { BrowserModule } from '@angular/platform-browser';  
import { NgModule } from '@angular/core';
import { AppRoutingModule } from './app-routing.module';  
import { AppComponent } from './app.component';  
import { HttpClientModule } from '@angular/common/http';

@NgModule({  
  declarations: [  
    AppComponent,  
  ],  
  imports: [  
    BrowserModule,  
    AppRoutingModule,  
    HttpClientModule  
  ],  
  providers: [],  
  bootstrap: [AppComponent]  
})  
export class AppModule { }
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接下来,生成一个组件:

$ ng generate component home
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接下来,生成一个上传服务:

$ ng generate service upload
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接下来,打开 src/app/upload.service.ts 文件如下:

import { HttpClient, HttpEvent, HttpErrorResponse, HttpEventType } from  '@angular/common/http';  
import { map } from  'rxjs/operators';

@Injectable({  
  providedIn: 'root'  
})  
export class UploadService { 
    SERVER_URL: string = "https://file.io/";  
    constructor(private httpClient: HttpClient) { }
    public upload(formData) {

      return this.httpClient.post<any>(this.SERVER_URL, formData, {  
         reportProgress: true,  
         observe: 'events'  
      });  
   }
}
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接下来,打开 src/app/home/home.component.ts 文件,并开始添加以下导入:

import { Component, OnInit, ViewChild, ElementRef  } from '@angular/core';
import { HttpEventType, HttpErrorResponse } from '@angular/common/http';
import { of } from 'rxjs';  
import { catchError, map } from 'rxjs/operators';  
import { UploadService } from  '../upload.service';
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接下来,定义 fileUpload 和 files 变量并注入 UploadService 如下:

@Component({  
  selector: 'app-home',  
  templateUrl: './home.component.html',  
  styleUrls: ['./home.component.css']  
})  
export class HomeComponent implements OnInit {
    @ViewChild("fileUpload", {static: false}) fileUpload: ElementRef;files  = [];  
    constructor(private uploadService: UploadService) { }
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接下来,定义 uploadFile() 方法:

uploadFile(file) {  
    const formData = new FormData();  
    formData.append('file', file.data);  
    file.inProgress = true;  
    this.uploadService.upload(formData).pipe(  
      map(event => {  
        switch (event.type) {  
          case HttpEventType.UploadProgress:  
            file.progress = Math.round(event.loaded * 100 / event.total);  
            break;  
          case HttpEventType.Response:  
            return event;  
        }  
      }),  
      catchError((error: HttpErrorResponse) => {  
        file.inProgress = false;  
        return of(`${file.data.name} upload failed.`);  
      })).subscribe((event: any) => {  
        if (typeof (event) === 'object') {  
          console.log(event.body);  
        }  
      });  
  }
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接下来,定义uploadFiles() 方法,该方法可用于上传多个图像文件:

private uploadFiles() {  
    this.fileUpload.nativeElement.value = '';  
    this.files.forEach(file => {  
      this.uploadFile(file);  
    });  
}
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接下来,定义 onClick() 方法:

onClick() {  
    const fileUpload = this.fileUpload.nativeElement;fileUpload.onchange = () => {  
    for (let index = 0; index < fileUpload.files.length; index++)  
    {  
     const file = fileUpload.files[index];  
     this.files.push({ data: file, inProgress: false, progress: 0});  
    }  
      this.uploadFiles();  
    };  
    fileUpload.click();  
}
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接下来,我们需要创建图片上传 UI 的 HTML 模板。打开 src/app/home/home.component.html 文件,添加以下内容:

import { BrowserModule } from '@angular/platform-browser';  
import { NgModule } from '@angular/core';
import { AppRoutingModule } from './app-routing.module';  
import { AppComponent } from './app.component';  
import { HttpClientModule } from '@angular/common/http';

@NgModule({  
  declarations: [  
    AppComponent,  
  ],  
  imports: [  
    BrowserModule,  
    AppRoutingModule,  
    HttpClientModule  
  ],  
  providers: [],  
  bootstrap: [AppComponent]  
})  
export class AppModule { }
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看看这个教程和这篇文章


tru*_*oda 9

非常简单快捷的方法是使用ng2-file-upload

通过npm安装ng2-file-upload。 npm i ng2-file-upload --save

首先,在模块中导入模块。

import { FileUploadModule } from 'ng2-file-upload';

Add it to [imports] under @NgModule:
imports: [ ... FileUploadModule, ... ]
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标记:

<input ng2FileSelect type="file" accept=".xml" [uploader]="uploader"/>
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在您的ts中:

import { FileUploader } from 'ng2-file-upload';
...
uploader: FileUploader = new FileUploader({ url: "api/your_upload", removeAfterUpload: false, autoUpload: true });
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这是最简单的用法。要了解所有功能,请参阅演示

  • 图片上传后如何获得回应?会有什么反应,文档缺少这一部分。 (2认同)
  • 警告:ng2-file-upload 不使用 Angular 的 http 服务,因此 MSAL 拦截器不会拾取调用,因此访问令牌不会自动添加到授权标头。 (2认同)

小智 9

好的,由于此线程出现在 google 的第一个结果中,并且对于其他有相同问题的用户,您不必像 trueboroda 所指出的那样重新启动轮子,有 ng2-file-upload 库可以简化上传文件的过程角度为 6 和 7 的文件,您需要做的就是:

安装最新的 Angular CLI

yarn add global @angular/cli
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然后安装 rx-compat 考虑兼容性问题

npm install rxjs-compat --save
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安装 ng2-file-upload

npm install ng2-file-upload --save
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在您的模块中导入 FileSelectDirective 指令。

import { FileSelectDirective } from 'ng2-file-upload';

Add it to [declarations] under @NgModule:
declarations: [ ... FileSelectDirective , ... ]
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在您的组件中

import { FileUploader } from 'ng2-file-upload/ng2-file-upload';
...

export class AppComponent implements OnInit {

   public uploader: FileUploader = new FileUploader({url: URL, itemAlias: 'photo'});
}
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模板

<input type="file" name="photo" ng2FileSelect [uploader]="uploader" />
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为了更好地理解,您可以查看此链接: 如何使用 Angular 6/7 上传文件


Dan*_*cki 7

就我个人而言,我在前端使用ngx-material-file-input,后端使用Firebase。更准确地说用于后端的Firebase 的C响亮存储与 Cloud Firestore 相结合。下面是一个示例,它限制文件不大于 20 MB,并且只接受某些文件扩展名。我还使用Cloud Firestore来存储上传文件的链接,但您可以跳过此步骤。

联系方式.component.html

<mat-form-field>
  <!--
    Accept only files in the following format: .doc, .docx, .jpg, .jpeg, .pdf, .png, .xls, .xlsx. However, this is easy to bypass, Cloud Storage rules has been set up on the back-end side.
  -->
  <ngx-mat-file-input
    [accept]="[
      '.doc',
      '.docx',
      '.jpg',
      '.jpeg',
      '.pdf',
      '.png',
      '.xls',
      '.xlsx'
    ]"
    (change)="uploadFile($event)"
    formControlName="fileUploader"
    multiple
    aria-label="Here you can add additional files about your project, which can be helpeful for us."
    placeholder="Additional files"
    title="Additional files"
    type="file"
  >
  </ngx-mat-file-input>
  <mat-icon matSuffix>folder</mat-icon>
  <mat-hint
    >Accepted formats: DOC, DOCX, JPG, JPEG, PDF, PNG, XLS and XLSX,
    maximum files upload size: 20 MB.
  </mat-hint>
  <!--
    Non-null assertion operators are required to let know the compiler that this value is not empty and exists.
  -->
  <mat-error
    *ngIf="contactForm.get('fileUploader')!.hasError('maxContentSize')"
  >
    This size is too large,
    <strong
      >maximum acceptable upload size is
      {{
        contactForm.get('fileUploader')?.getError('maxContentSize')
          .maxSize | byteFormat
      }}</strong
    >
    (uploaded size:
    {{
      contactForm.get('fileUploader')?.getError('maxContentSize')
        .actualSize | byteFormat
    }}).
  </mat-error>
</mat-form-field>
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contact.component.ts(尺寸验证器部分)

import { FileValidator } from 'ngx-material-file-input';
import { FormBuilder, FormGroup, Validators } from '@angular/forms';

/**
 * @constructor
 * @description Creates a new instance of this component.
 * @param  {formBuilder} - an abstraction class object to create a form group control for the contact form.
 */
constructor(
  private angularFirestore: AngularFirestore,
  private angularFireStorage: AngularFireStorage,
  private formBuilder: FormBuilder
) {}

public maxFileSize = 20971520;
public contactForm: FormGroup = this.formBuilder.group({
    fileUploader: [
      '',
      Validators.compose([
        FileValidator.maxContentSize(this.maxFileSize),
        Validators.maxLength(512),
        Validators.minLength(2)
      ])
    ]
})
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contact.component.ts(文件上传部分)

import { AngularFirestore } from '@angular/fire/firestore';
import {
  AngularFireStorage,
  AngularFireStorageReference,
  AngularFireUploadTask
} from '@angular/fire/storage';
import { catchError, finalize } from 'rxjs/operators';
import { throwError } from 'rxjs';

public downloadURL: string[] = [];
/**
* @description Upload additional files to Cloud Firestore and get URL to the files.
   * @param {event} - object of sent files.
   * @returns {void}
   */
  public uploadFile(event: any): void {
    // Iterate through all uploaded files.
    for (let i = 0; i < event.target.files.length; i++) {
      const randomId = Math.random()
        .toString(36)
        .substring(2); // Create random ID, so the same file names can be uploaded to Cloud Firestore.

      const file = event.target.files[i]; // Get each uploaded file.

      // Get file reference.
      const fileRef: AngularFireStorageReference = this.angularFireStorage.ref(
        randomId
      );

      // Create upload task.
      const task: AngularFireUploadTask = this.angularFireStorage.upload(
        randomId,
        file
      );

      // Upload file to Cloud Firestore.
      task
        .snapshotChanges()
        .pipe(
          finalize(() => {
            fileRef.getDownloadURL().subscribe((downloadURL: string) => {
              this.angularFirestore
                .collection(process.env.FIRESTORE_COLLECTION_FILES!) // Non-null assertion operator is required to let know the compiler that this value is not empty and exists.
                .add({ downloadURL: downloadURL });
              this.downloadURL.push(downloadURL);
            });
          }),
          catchError((error: any) => {
            return throwError(error);
          })
        )
        .subscribe();
    }
  }
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存储规则

rules_version = '2';
service firebase.storage {
  match /b/{bucket}/o {
    match /{allPaths=**} {
        allow read; // Required in order to send this as attachment.
      // Allow write files Firebase Storage, only if:
      // 1) File is no more than 20MB
      // 2) Content type is in one of the following formats: .doc, .docx, .jpg, .jpeg, .pdf, .png, .xls, .xlsx.
      allow write: if request.resource.size <= 20 * 1024 * 1024
        && (request.resource.contentType.matches('application/msword')
        || request.resource.contentType.matches('application/vnd.openxmlformats-officedocument.wordprocessingml.document')
        || request.resource.contentType.matches('image/jpg')
        || request.resource.contentType.matches('image/jpeg')
        || request.resource.contentType.matches('application/pdf')
                || request.resource.contentType.matches('image/png')
        || request.resource.contentType.matches('application/vnd.ms-excel')
        || request.resource.contentType.matches('application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'))
    }
  }
}
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  • 看起来不错,但是为什么在 contactForm 声明中需要 `toString()` 呢? (2认同)

小智 6

我使用的是Angular 5.2.11,我喜欢Gregor Doroschenko提供的解决方案,但是我注意到上载的文件为零字节,我必须做一些小改动才能使它适合我。

postFile(fileToUpload: File): Observable<boolean> {
  const endpoint = 'your-destination-url';
  return this.httpClient
    .post(endpoint, fileToUpload, { headers: yourHeadersConfig })
    .map(() => { return true; })
    .catch((e) => this.handleError(e));
}
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以下几行(formData)对我不起作用。

const formData: FormData = new FormData();
formData.append('fileKey', fileToUpload, fileToUpload.name);
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https://github.com/amitrke/ngrke/blob/master/src/app/services/fileupload.service.ts


Roh*_*rte 6

使用 Angular 和 nodejs(express) 上传文件的完整示例

HTML代码

            <div class="form-group">
                <label for="file">Choose File</label><br/>
                <input type="file" id="file" (change)="uploadFile($event.target.files)" multiple>
            </div>
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TS 组件代码

uploadFile(files) {
    console.log('files', files)
        var formData = new FormData();

    for(let i =0; i < files.length; i++){
      formData.append("files", files[i], files[i]['name']);
        }

    this.httpService.httpPost('/fileUpload', formData)
      .subscribe((response) => {
        console.log('response', response)
      },
        (error) => {
      console.log('error in fileupload', error)
       })
  }
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节点 Js 代码

文件上传 API 控制器

function start(req, res) {
fileUploadService.fileUpload(req, res)
    .then(fileUploadServiceResponse => {
        res.status(200).send(fileUploadServiceResponse)
    })
    .catch(error => {
        res.status(400).send(error)
    })
}

module.exports.start = start
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使用multer上传服务

const multer = require('multer') // import library
const moment = require('moment')
const q = require('q')
const _ = require('underscore')
const fs = require('fs')
const dir = './public'

/** Store file on local folder */
let storage = multer.diskStorage({
destination: function (req, file, cb) {
    cb(null, 'public')
},
filename: function (req, file, cb) {
    let date = moment(moment.now()).format('YYYYMMDDHHMMSS')
    cb(null, date + '_' + file.originalname.replace(/-/g, '_').replace(/ /g,     '_'))
}
})

/** Upload files  */
let upload = multer({ storage: storage }).array('files')

/** Exports fileUpload function */
module.exports = {
fileUpload: function (req, res) {
    let deferred = q.defer()

    /** Create dir if not exist */
    if (!fs.existsSync(dir)) {
        fs.mkdirSync(dir)
        console.log(`\n\n ${dir} dose not exist, hence created \n\n`)
    }

    upload(req, res, function (err) {
        if (req && (_.isEmpty(req.files))) {
            deferred.resolve({ status: 200, message: 'File not attached', data: [] })
        } else {
            if (err) {
                deferred.reject({ status: 400, message: 'error', data: err })
            } else {
                deferred.resolve({
                    status: 200,
                    message: 'File attached',
                    filename: _.pluck(req.files,
                        'filename'),
                    data: req.files
                })
            }
        }
    })
    return deferred.promise
}
}
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Cod*_*Spy 5

角度7/8/9

来源链接

在此输入图像描述

使用引导表单

<form>
    <div class="form-group">
        <fieldset class="form-group">

            <label>Upload Logo</label>
            {{imageError}}
            <div class="custom-file fileInputProfileWrap">
                <input type="file" (change)="fileChangeEvent($event)" class="fileInputProfile">
                <div class="img-space">

                    <ng-container *ngIf="isImageSaved; else elseTemplate">
                        <img [src]="cardImageBase64" />
                    </ng-container>
                    <ng-template #elseTemplate>

                        <img src="./../../assets/placeholder.png" class="img-responsive">
                    </ng-template>

                </div>

            </div>
        </fieldset>
    </div>
    <a class="btn btn-danger" (click)="removeImage()" *ngIf="isImageSaved">Remove</a>
</form>
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在组件类

fileChangeEvent(fileInput: any) {
    this.imageError = null;
    if (fileInput.target.files && fileInput.target.files[0]) {
        // Size Filter Bytes
        const max_size = 20971520;
        const allowed_types = ['image/png', 'image/jpeg'];
        const max_height = 15200;
        const max_width = 25600;

        if (fileInput.target.files[0].size > max_size) {
            this.imageError =
                'Maximum size allowed is ' + max_size / 1000 + 'Mb';

            return false;
        }

        if (!_.includes(allowed_types, fileInput.target.files[0].type)) {
            this.imageError = 'Only Images are allowed ( JPG | PNG )';
            return false;
        }
        const reader = new FileReader();
        reader.onload = (e: any) => {
            const image = new Image();
            image.src = e.target.result;
            image.onload = rs => {
                const img_height = rs.currentTarget['height'];
                const img_width = rs.currentTarget['width'];

                console.log(img_height, img_width);


                if (img_height > max_height && img_width > max_width) {
                    this.imageError =
                        'Maximum dimentions allowed ' +
                        max_height +
                        '*' +
                        max_width +
                        'px';
                    return false;
                } else {
                    const imgBase64Path = e.target.result;
                    this.cardImageBase64 = imgBase64Path;
                    this.isImageSaved = true;
                    // this.previewImagePath = imgBase64Path;
                }
            };
        };

        reader.readAsDataURL(fileInput.target.files[0]);
    }
}

removeImage() {
    this.cardImageBase64 = null;
    this.isImageSaved = false;
}
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小智 5

这是我上传excel文件的方法:
目录结构:

app
|-----uploadcomponent
           |-----uploadcomponent.module.ts
           |-----uploadcomponent.html
|-----app.module.ts
|-----app.component.ts
|-----app.service.ts
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上传组件.html

<div>
   <form [formGroup]="form" (ngSubmit)="onSubmit()">
     <input type="file" name="profile"  enctype="multipart/form-data" accept=".xlsm,application/msexcel" (change)="onChange($event)" />
     <button type="submit">Upload Template</button>
     <button id="delete_button" class="delete_button" type="reset"><i class="fa fa-trash"></i></button> 
   </form>           
</div>
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上传组件.ts

    import { FormBuilder, FormGroup, ReactiveFormsModule } from '@angular/forms';
    import { Component, OnInit } from '@angular/core';
    ....
    export class UploadComponent implements OnInit {
        form: FormGroup;
        constructor(private formBuilder: FormBuilder, private uploadService: AppService) {}
        ngOnInit() {  
            this.form = this.formBuilder.group({
               profile: ['']
            });
        }

        onChange(event) {
            if (event.target.files.length > 0) {
              const file = event.target.files[0];

              this.form.get('profile').setValue(file);
              console.log(this.form.get('profile').value)
            }
        }

        onSubmit() {
           const formData = new FormData();
           formData.append('file', this.form.get('profile').value);

           this.uploadService.upload(formData).subscribe(
             (res) => {
               this.response = res;

               console.log(res);

             },
             (err) => {  
               console.log(err);
             });
         }
    }
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应用服务.ts

    upload(formData) {
        const endpoint = this.service_url+'upload/';
        const httpOptions = headers: new HttpHeaders({    <<<< Changes are here
            'Authorization': 'token xxxxxxx'})
        };
        return this.http.post(endpoint, formData, httpOptions);
    }
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在后端,我使用 DJango REST 框架。
模型.py

from __future__ import unicode_literals
from django.db import models
from django.db import connection
from django_mysql.models import JSONField, Model
import uuid
import os


def change_filename(instance, filename):
    extension = filename.split('.')[-1]
    file_name = os.path.splitext(filename)[0]
    uuid_name = uuid.uuid4()
    return file_name+"_"+str(uuid_name)+"."+extension

class UploadTemplate (Model):
    id = models.AutoField(primary_key=True)
    file = models.FileField(blank=False, null=False, upload_to=change_filename)

    def __str__(self):
        return str(self.file.name)
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视图.py。

class UploadView(APIView):
    serializer_class = UploadSerializer
    parser_classes = [MultiPartParser]       

    def get_queryset(self):
        queryset = UploadTemplate.objects.all()
        return queryset

    def post(self, request, *args, **kwargs):
        file_serializer = UploadSerializer(data=request.data)
        status = None
        message = None
        if file_serializer.is_valid():
            file_serializer.save()
            status = "Success"
            message = "Success"
        else:
            status = "Failure"
            message = "Failure!"
        content = {'status': status, 'message': message}
        return Response(content)
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序列化器.py。

from uploadtemplate.models import UploadTemplate
from rest_framework import serializers

class UploadSerializer(serializers.ModelSerializer):
    class Meta:
        model = UploadTemplate
        fields = '__all__'   
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网址.py。

router.register(r'uploadtemplate', uploadtemplateviews.UploadTemplateView, 
    base_name='UploadTemplate')
urlpatterns = [
    ....
    url(r'upload/', uploadtemplateviews.UploadTemplateView.as_view()),
] + static(settings.STATIC_URL, document_root=settings.STATIC_ROOT)

if settings.DEBUG:
    urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)
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MEDIA_URL 和 MEDIA_ROOT 在项目的 settings.py 中定义。

谢谢!