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
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
其他回答
使用Angular和nodejs上传文件的完整示例(express)
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>
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)
})
}
Node Js代码
上传火灾控制器
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
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 ${dir} dose not exist, hence created \n\n`)
}
upload(req, res, function (err) {
if (req && (_.isEmpty(req.files))) {
deferred.resolve({ status: 200, message: 'File not attached', data: [] })
} else {
if (err) {
deferred.reject({ status: 400, message: 'error', data: err })
} else {
deferred.resolve({
status: 200,
message: 'File attached',
filename: _.pluck(req.files,
'filename'),
data: req.files
})
}
}
})
return deferred.promise
}
}
超文本标记语言
<div class="form-group">
<label for="file">Choose File</label><br /> <input type="file" id="file" (change)="uploadFiles($event.target.files)">
</div>
<button type="button" (click)="RequestUpload()">Ok</button>
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(( ) => {
});
}
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";
}
}
我们必须在C驱动器中创建一个文件夹“temp”,然后这段代码将在控制台中打印Json并将上传的文件保存在创建的文件夹中
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>
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
通过这种方式,我实现了在项目中上传文件到web API。
我为谁分担关心。
const formData: FormData = new FormData();
formData.append('Image', image, image.name);
formData.append('ComponentId', componentId);
return this.http.post('/api/dashboard/UploadImage', formData);
一步一步
ASP。网上广告
[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);
}
}
HTML表单
<form #imageForm=ngForm (ngSubmit)="OnSubmit(Image)">
<img [src]="imageUrl" class="imgArea">
<div class="image-upload">
<label for="file-input">
<img src="upload.jpg" />
</label>
<input id="file-input" #Image type="file" (change)="handleFileInput($event.target.files)" />
<button type="submit" class="btn-large btn-submit" [disabled]="Image.value=='' || !imageForm.valid"><i
class="material-icons">save</i></button>
</div>
</form>
TS文件使用API
OnSubmit(Image) {
this.dashboardService.uploadImage(this.componentId, this.fileToUpload).subscribe(
data => {
console.log('done');
Image.value = null;
this.imageUrl = "/assets/img/logo.png";
}
);
}
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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