我是Angular的初学者，我想知道如何创建Angular 5文件上传部分，我试图找到任何教程或文档，但我在任何地方都看不到任何东西。对此有什么想法吗?我尝试了ng4-files，但它不适用于Angular 5
当前回答
首先，你需要在你的Angular项目中设置HttpClient。
打开src/app/app.module。导入HttpClientModule并将其添加到模块的imports数组中，如下所示:
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 { }
接下来，生成一个组件:
$ ng generate component home
接下来，生成一个上传服务:
$ ng generate service upload
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'
});
}
}
接下来，打开src/app/home/home.component.ts文件，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';
接下来，定义fileUpload和files变量，并注入UploadService，如下所示:
@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) { }
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(`${file.data.name} upload failed.`);
})).subscribe((event: any) => {
if (typeof (event) === 'object') {
console.log(event.body);
}
});
}
接下来，定义uploadFiles()方法，该方法可用于上传多个图像文件:
private uploadFiles() {
this.fileUpload.nativeElement.value = '';
this.files.forEach(file => {
this.uploadFile(file);
});
}
接下来，定义onClick()方法:
onClick() {
const fileUpload = this.fileUpload.nativeElement;fileUpload.onchange = () => {
for (let index = 0; index < fileUpload.files.length; index++)
{
const file = fileUpload.files[index];
this.files.push({ data: file, inProgress: false, progress: 0});
}
this.uploadFiles();
};
fileUpload.click();
}
接下来，我们需要创建图像上传UI的HTML模板。打开src/app/home/home.component.html文件，添加以下内容:
<div [ngStyle]="{'text-align':center; 'margin-top': 100px;}">
<button mat-button color="primary" (click)="fileUpload.click()">choose file</button>
<button mat-button color="warn" (click)="onClick()">Upload</button>
<input [hidden]="true" type="file" #fileUpload id="fileUpload" name="fileUpload" multiple="multiple" accept="image/*" />
</div>
看看这篇教程和这篇文章
其他回答
在Angular 7/8/9中
来源链接
使用自举表单
<form>
<div class="form-group">
<fieldset class="form-group">
<label>Upload Logo</label>
{{imageError}}
<div class="custom-file fileInputProfileWrap">
<input type="file" (change)="fileChangeEvent($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>
在组件类中
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;
}
首先，你需要在你的Angular项目中设置HttpClient。
打开src/app/app.module。导入HttpClientModule并将其添加到模块的imports数组中，如下所示:
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 { }
接下来，生成一个组件:
$ ng generate component home
接下来，生成一个上传服务:
$ ng generate service upload
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'
});
}
}
接下来，打开src/app/home/home.component.ts文件，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';
接下来，定义fileUpload和files变量，并注入UploadService，如下所示:
@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) { }
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(`${file.data.name} upload failed.`);
})).subscribe((event: any) => {
if (typeof (event) === 'object') {
console.log(event.body);
}
});
}
接下来，定义uploadFiles()方法，该方法可用于上传多个图像文件:
private uploadFiles() {
this.fileUpload.nativeElement.value = '';
this.files.forEach(file => {
this.uploadFile(file);
});
}
接下来，定义onClick()方法:
onClick() {
const fileUpload = this.fileUpload.nativeElement;fileUpload.onchange = () => {
for (let index = 0; index < fileUpload.files.length; index++)
{
const file = fileUpload.files[index];
this.files.push({ data: file, inProgress: false, progress: 0});
}
this.uploadFiles();
};
fileUpload.click();
}
接下来，我们需要创建图像上传UI的HTML模板。打开src/app/home/home.component.html文件，添加以下内容:
<div [ngStyle]="{'text-align':center; 'margin-top': 100px;}">
<button mat-button color="primary" (click)="fileUpload.click()">choose file</button>
<button mat-button color="warn" (click)="onClick()">Upload</button>
<input [hidden]="true" type="file" #fileUpload id="fileUpload" name="fileUpload" multiple="multiple" accept="image/*" />
</div>
看看这篇教程和这篇文章
下面是我上传excel文件的方法: 目录结构:
app
|-----uploadcomponent
|-----uploadcomponent.module.ts
|-----uploadcomponent.html
|-----app.module.ts
|-----app.component.ts
|-----app.service.ts
uploadcomponent.html
<div>
<form [formGroup]="form" (ngSubmit)="onSubmit()">
<input type="file" name="profile" enctype="multipart/form-data" accept=".xlsm,application/msexcel" (change)="onChange($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>
uploadcomponent.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);
});
}
}
app.service.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);
}
在后台，我使用DJango REST框架。 models.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)
views.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)
serializers.py。
from uploadtemplate.models import UploadTemplate
from rest_framework import serializers
class UploadSerializer(serializers.ModelSerializer):
class Meta:
model = UploadTemplate
fields = '__all__'
urls . 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)
MEDIA_URL和MEDIA_ROOT在项目的settings.py中定义。
谢谢!
试试这个
安装
npm install primeng --save
进口
import {FileUploadModule} from 'primeng/primeng';
Html
<p-fileUpload name="myfile[]" url="./upload.php" multiple="multiple"
accept="image/*" auto="auto"></p-fileUpload>
create-profile.html
<body>
<h1 class="font-weight-bold" >Create Advertistment</h1>
<hr />
<form [formGroup]="form" (submit)="onSubmit()">
<div>
<label class="font-weight-bold">Insert Subject name</label>
<br>
<input formControlName="name" type="text" placeholder="Enter name..." />
</div>
<div>
<br>
<label class="font-weight-bold">Select the Advertistment</label>
<br>
<input (change)="onFileSelect($event)" type="file" />
</div>
<br>
<!--<div *ngIf="imageData">
<img [src]="imageData" [alt]="form.value.name" />
</div>-->
<div>
<label class="font-weight-bold">Upload the Advertistment</label>
<br>
<button type="submit" class="btn btn-success" >Upload Advertistment</button>
</div>
</form>
</body>
create-profile.ts
import { Component, OnInit } from "@angular/core";
import { FormGroup, FormControl } from "@angular/forms";
import { Profile } from "../../models/Profile";
import { ProfileService } from "src/app/services/profile.service";
@Component({
selector: "app-create-profile",
templateUrl: "./create-profile.component.html",
styleUrls: ["./create-profile.component.css"],
})
export class CreateProfileComponent implements OnInit {
form: FormGroup;
profile: Profile;
imageData: string;
constructor(private profileService: ProfileService) {}
ngOnInit(): void {
this.form = new FormGroup({
name: new FormControl(null),
image: new FormControl(null),
});
}
onFileSelect(event: Event) {
const file = (event.target as HTMLInputElement).files[0];
this.form.patchValue({ image: file });
const allowedMimeTypes = ["image/png", "image/jpeg", "image/jpg"];
if (file && allowedMimeTypes.includes(file.type)) {
const reader = new FileReader();
reader.onload = () => {
this.imageData = reader.result as string;
};
reader.readAsDataURL(file);
}
}
onSubmit() {
this.profileService.addProfile(this.form.value.name, this.form.value.image);
this.form.reset();
this.imageData = null;
}
}
profile.service.ts
import { Injectable } from "@angular/core";
import { HttpClient } from "@angular/common/http";
import { map } from "rxjs/operators";
import { Profile } from "../models/Profile";
import { Subject } from "rxjs";
@Injectable({
providedIn: "root",
})
export class ProfileService {
private profiles: Profile[] = [];
private profiles$ = new Subject<Profile[]>();
readonly url = "http://localhost:3000/api/profiles";
constructor(private http: HttpClient) {}
getProfiles() {
this.http
.get<{ profiles: Profile[] }>(this.url)
.pipe(
map((profileData) => {
return profileData.profiles;
})
)
.subscribe((profiles) => {
this.profiles = profiles;
this.profiles$.next(this.profiles);
});
}
getProfilesStream() {
return this.profiles$.asObservable();
}
addProfile(name: string, image: File): void {
const profileData = new FormData();
profileData.append("name", name);
profileData.append("image", image, name);
this.http
.post<{ profile: Profile }>(this.url, profileData)
.subscribe((profileData) => {
const profile: Profile = {
_id: profileData.profile._id,
name: name,
imagePath: profileData.profile.imagePath,
};
this.profiles.push(profile);
this.profiles$.next(this.profiles);
});
}
}
Profile.ts
export interface Profile {
_id: string;
name: string;
imagePath: string;
}
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