如何在Angular2中上传文件

Question

我必须提交一份表格和图片.我试过这个代码(有多种方式),但对我来说不起作用.有没有人有使用angular2上传文件的工作演示请帮助我.

component.html

    <form class="form-horizontal" role="form" >

        <div class="form-group">
            <label class="control-label col-sm-4" for="myname" style="">Name<span class="asterisk">*</span></label>
            <div class="col-sm-7">
                <div>
                    <input type="text" class="form-control" id="myname"
                    [(ngModel)]="myfile.name">                        
                </div>                  
            </div>                               
        </div>        


        <div class="form-group">
            <label class="control-label col-sm-4" for="myimage">Image</label>
            <div class="col-sm-7">
                <div>
                    <input type="file" (change)="fileChangeEvent($event)" placeholder="Upload file..." />                         
                </div>   
            </div>
        </div>


        <div class="form-group">        
        <div class="text-center">
            <button type="button" (click)="upload()">Upload</button>             
        </div>
        </div>
  </form>

component.ts

     myfile={
                "name":"Mubashshir",               
                "image":''
     }

     fileChangeEvent(fileInput: any){
        this.myfile.image = fileInput.target.files;        
     }

     upload(){
          this.base_path_service.PostRequest('http://128.199.190.109/api/school/schoolDetail/',this.myfile)
            .subscribe(
                data => {
                            console.log("data submitted");                        
                        },
                err => console.log(err),
                () =>{
                     console.log('Authentication Complete');                    

                }
            );
      }

Answer 1

事实上,Http班级目前不支持这一点.

您需要利用底层XHR对象来执行此操作:

import {Injectable} from 'angular2/core';
import {Observable} from 'rxjs/Rx';

@Injectable()
export class UploadService {
  constructor () {
    this.progress$ = Observable.create(observer => {
      this.progressObserver = observer
    }).share();
  }

  private makeFileRequest (url: string, params: string[], files: File[]): Observable {
    return Observable.create(observer => {
      let formData: FormData = new FormData(),
        xhr: XMLHttpRequest = new XMLHttpRequest();

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

      xhr.onreadystatechange = () => {
        if (xhr.readyState === 4) {
          if (xhr.status === 200) {
            observer.next(JSON.parse(xhr.response));
            observer.complete();
          } else {
            observer.error(xhr.response);
          }
        }
      };

      xhr.upload.onprogress = (event) => {
        this.progress = Math.round(event.loaded / event.total * 100);

        this.progressObserver.next(this.progress);
      };

      xhr.open('POST', url, true);
      xhr.send(formData);
    });
  }
}

有关详细信息,请参阅此plunkr:https://plnkr.co/edit/ozZqbxIorjQW15BrDFrg？p = info .

在Angular回购中有一个问题和待决公关:

• https://github.com/angular/angular/issues/10424
• https://github.com/angular/angular/pull/7310/files

Answer 2

你的http服务文件:

import { Injectable } from "@angular/core";
import { ActivatedRoute, Router } from '@angular/router';
import { Http, Headers, Response, Request, RequestMethod, URLSearchParams, RequestOptions } from "@angular/http";
import {Observable} from 'rxjs/Rx';
import { Constants } from './constants';
declare var $: any;

@Injectable()
export class HttpClient {
  requestUrl: string;
  responseData: any;
  handleError: any;

  constructor(private router: Router, 
  private http: Http, 
  private constants: Constants, 
  ) {
    this.http = http;
  }

  postWithFile (url: string, postData: any, files: File[]) {

    let headers = new Headers();
    let formData:FormData = new FormData();
    formData.append('files', files[0], files[0].name);
    // For multiple files
    // for (let i = 0; i < files.length; i++) {
    //     formData.append(`files[]`, files[i], files[i].name);
    // }

    if(postData !=="" && postData !== undefined && postData !==null){
      for (var property in postData) {
          if (postData.hasOwnProperty(property)) {
              formData.append(property, postData[property]);
          }
      }
    }
    var returnReponse = new Promise((resolve, reject) => {
      this.http.post(this.constants.root_dir + url, formData, {
        headers: headers
      }).subscribe(
          res => {
            this.responseData = res.json();
            resolve(this.responseData);
          },
          error => {
            this.router.navigate(['/login']);
            reject(error);
          }
      );
    });
    return returnReponse;
  }
}

调用你的函数(组件文件):

onChange(event) {
    let file = event.srcElement.files;
    let postData = {field1:"field1", field2:"field2"}; // Put your form data variable. This is only example.
    this._service.postWithFile(this.baseUrl + "add-update",postData,file).then(result => {
        console.log(result);
    });
}

你的HTML代码:

<input type="file" class="form-control" name="documents" (change)="onChange($event)" [(ngModel)]="stock.documents" #documents="ngModel">