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
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!
其他回答
非常简单和最快的方法是使用ng2-file-upload。
通过npm安装ng2-file-upload。NPM I ng2-file-upload——保存
首先在模块中导入模块。
import { FileUploadModule } from 'ng2-file-upload';
Add it to [imports] under @NgModule:
imports: [ ... FileUploadModule, ... ]
标记:
<input ng2FileSelect type="file" accept=".xml" [uploader]="uploader"/>
在你的组件中:
import { FileUploader } from 'ng2-file-upload';
...
uploader: FileUploader = new FileUploader({ url: "api/your_upload", removeAfterUpload: false, autoUpload: true });
这是最简单的用法。要知道所有的权力，这看到演示
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!
下面是一个上传文件到api的例子:
步骤1:HTML模板
定义文件类型的简单输入标记。为(change)-event添加一个处理选择文件的函数。
<div class="form-group">
<label for="file">Choose File</label>
<input type="file"
id="file"
(change)="handleFileInput($event.target.files)">
</div>
步骤2:在TypeScript中处理上传
为所选文件定义一个默认变量。
fileToUpload: File | null = null;
创建你在(change)-event中使用的函数:
handleFileInput(files: FileList) {
this.fileToUpload = files.item(0);
}
如果你想处理多文件选择，那么你可以遍历这个文件数组。
现在通过调用file-upload.service创建文件上传函数:
uploadFileToActivity() {
this.fileUploadService.postFile(this.fileToUpload).subscribe(data => {
// do something, if upload success
}, error => {
console.log(error);
});
}
第三步:文件上传服务
通过post方法上传文件，你应该使用FormData，因为这样你可以添加文件到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));
}
所以，这是一个非常简单的工作例子，我每天都在工作中使用。
我使用的是Angular 5.2.11， 我喜欢Gregor Doroschenko提供的解决方案，但是我注意到上传的文件是零字节的，我必须做一个小小的改变才能让它为我工作。
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));
}
下面几行(formData)对我不起作用。
const formData: FormData = new FormData();
formData.append('fileKey', fileToUpload, fileToUpload.name);
https://github.com/amitrke/ngrke/blob/master/src/app/services/fileupload.service.ts
好的，因为这个线程出现在谷歌的第一个结果中，对于其他有同样问题的用户，你不需要像trueboroda指出的那样重新开始，有ng2-file-upload库，它简化了使用angular 6和7上传文件的过程，你所需要做的是:
安装最新的Angular CLI
yarn add global @angular/cli
出于兼容性考虑，请安装rx-compat
npm install rxjs-compat --save
安装ng2-file-upload
npm install ng2-file-upload --save
在你的模块中导入FileSelectDirective指令。
import { FileSelectDirective } from 'ng2-file-upload';
Add it to [declarations] under @NgModule:
declarations: [ ... FileSelectDirective , ... ]
在你的组件中
import { FileUploader } from 'ng2-file-upload/ng2-file-upload';
...
export class AppComponent implements OnInit {
public uploader: FileUploader = new FileUploader({url: URL, itemAlias: 'photo'});
}
模板
<input type="file" name="photo" ng2FileSelect [uploader]="uploader" />
为了更好地理解，你可以查看这个链接: 如何使用Angular 6/7上传文件
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