angular ng2文件上传问题

Question

我正在尝试上传不同的文件。但是问题来了，当我第二次选择一个文件时，它被添加到 fileArray，它没有被替换。

例如，我为第一个输入选择了一张图片。然后我决定为相同的输入选择不同的图片，然后它会被添加到一个文件数组中，所以当我上传它时，我不想上传的前一张图片也会被上传。

是否有任何解决方案（除了使用单个按钮上传多个文件外）以便当我第二次选择文件时它会被替换而不是添加到文件数组中？

uploadDocument.html 文件：

<form (ngSubmit)=f.form.valid && formSubmit() #f="ngForm">

        <input type="file" class="form-control ml-2" name="photo" ng2FileSelect [uploader]="uploader" />
          <input type="file" class="form-control ml-2" name="document1" ng2FileSelect [uploader]="uploader" />
            <input type="file" class="form-control ml-2" name="pic2" ng2FileSelect [uploader]="uploader" />

    <button type="submit" class="btn btn-danger btn-lg btn-fill">Upload</button>

</form>

uploadDocument.component.ts 文件：

import { Component, OnInit, Renderer, ElementRef } from '@angular/core';
import { UserService } from '../_services';
import { ActivatedRoute, Router, Params} from '@angular/router';
import { FileUploader } from 'ng2-file-upload/ng2-file-upload';
import { FileSelectDirective } from 'ng2-file-upload';

const URL = 'http://localhost:3002/api/upload';

@Component({
    selector: 'app-uploadDocument',
    templateUrl: './uploadDocument.component.html',
    styleUrls: ['./uploadDocument.component.scss']
})

export class UploadDocument implements OnInit {
    model: any = {};
    mobile: number;
    options: boolean;
    loading = false;
    public uploader:FileUploader = new FileUploader({url: URL});

    constructor(private userService: UserService, private route:ActivatedRoute,private router:Router, private el: ElementRef) { }

    ngOnInit() {


        this.uploader.onBeforeUploadItem = (item)=> {console.log("Item"); console.log(item)};

        this.uploader.onAfterAddingFile = (file)=> { file.withCredentials = false;};

       this.uploader.onCompleteItem = (item:any, response:any, status:any, headers:any) => {
             console.log("ImageUpload:uploaded:", item, status, response);
        };
    }

    formSubmit() {
        this.uploader.uploadAll();
    }

}

Answer 1

嗯，你可以显示队列，让用户管理（删除）文件。不是最优的，但它有效。

    <p class="files-uploaded" *ngFor="let item of uploader.queue">
      <strong>
        {{ item?.file?.name }} 
        <button type="button" class="btn btn-danger btn-xs"(click)="item.remove()">
          <span class="glyphicon glyphicon-trash"></span> Remove
        </button>
      </strong>
    </p>

Answer 2

我什至因此损失了几个小时。最后我做了一个调整来修复它。每当上传新文件时，上传队列将重置为仅存储最新文件 only.This 是在库提供的函数的 onAfterAddingFile 回调的帮助下完成的。下面是更改后的代码。

uploadDocument.component.ts 文件：

import { Component, OnInit, Renderer, ElementRef } from '@angular/core';
import { UserService } from '../_services';
import { ActivatedRoute, Router, Params} from '@angular/router';
import { FileUploader, FileItem } from 'ng2-file-upload';

const URL = 'http://localhost:3002/api/upload';

@Component({
    selector: 'app-uploadDocument',
    templateUrl: './uploadDocument.component.html',
    styleUrls: ['./uploadDocument.component.scss']
})

export class UploadDocument implements OnInit {
    model: any = {};
    mobile: number;
    options: boolean;
    loading = false;
    public uploader:FileUploader = new FileUploader({url: URL});

    constructor(private userService: UserService, private route:ActivatedRoute,private router:Router, private el: ElementRef) { }

    ngOnInit() {

         this.uploader.onAfterAddingFile = (fileItem: FileItem) => this.onAfterAddingFile(fileItem)

    }

    onAfterAddingFile(fileItem: FileItem) {
       let latestFile = this.uploader.queue[this.uploader.queue.length-1]
       this.uploader.queue = []; 
       this.uploader.queue.push(latestFile);
    }

    formSubmit() {
        this.uploader.uploadAll();
    }

}

希望对您有所帮助！

Answer 3

对我来说，前三个输入是必需的，其他三个输入是可选的，所以我这样做了，每个输入总是只接受 1 个文件，如果选择另一个文件，它将被替换：

import { Component, OnInit, ElementRef } from '@angular/core';
import { ActivatedRoute, Router, Params } from '@angular/router';
import { HttpClient } from '@angular/common/http';
import { ApiDomain } from '../url.constants';

const URL = ApiDomain+'/api/upload';

@Component({
    selector: 'app-uploadDocument',
    templateUrl: './uploadDocument.component.html',
    styleUrls: ['./uploadDocument.component.scss']
})

export class UploadDocument implements OnInit {
    model: any = {};
    id: string;
    options: boolean;
    loading = false;
    files = [];
    flag: number = 0;
    formData: FormData;
    filesArray: any;

    constructor(private el: ElementRef, private route: ActivatedRoute, private router: Router, private http: HttpClient) { }

    ngOnInit() {

        this.route.params.subscribe(
            (params: Params) => {
                this.id = params["id"];
                console.log(this.id);
            });

    }

    formSubmit() {
        this.loading = true;
        let inputEl: HTMLInputElement = this.el.nativeElement.querySelector('#tenththmarksheet');
        let inputEl1: HTMLInputElement = this.el.nativeElement.querySelector('#photo');
        let inputEl2: HTMLInputElement = this.el.nativeElement.querySelector('#aadharcard');
        let inputEl3: HTMLInputElement = this.el.nativeElement.querySelector('#caste');
        let inputEl4: HTMLInputElement = this.el.nativeElement.querySelector('#bhamasha');
        let inputEl5: HTMLInputElement = this.el.nativeElement.querySelector('#moolnivas');


        let fileCount: number = inputEl.files.length;
        let fileCount1: number = inputEl1.files.length;
        let fileCount2: number = inputEl2.files.length;
        let fileCount3: number = inputEl3.files.length;
        let fileCount4: number = inputEl4.files.length;
        let fileCount5: number = inputEl5.files.length;

        let formData = new FormData();

        if (fileCount > 0 && fileCount1 > 0 && fileCount2 > 0) {

            formData.append('id', this.id);
            formData.append('tenthmarksheet', inputEl.files.item(0));
            formData.append('photo', inputEl1.files.item(0));
            formData.append('aadhar', inputEl2.files.item(0));

            if (fileCount3 > 0) {
                formData.append('castecertificate', inputEl3.files.item(0));
            }
            if (fileCount4 > 0) {
                formData.append('bhamasha', inputEl4.files.item(0));
            }

            if (fileCount5 > 0) {
                formData.append('moolniwas', inputEl5.files.item(0));
            }

            this.http.post(URL, formData).subscribe(
                (complete) => {
                    this.loading = false;    
                    this.router.navigate(['/thankyou']);
                },
                (error) => {
                    console.log(error);
                    this.loading = false;
                });
        }

    }

}

angular ng2文件上传问题

angular ng2 file upload issue

angular

angular5

multer

ng2-file-upload