尽量不要设置options参数

这个http post(美元(this。apiEndPoint), formData)

并且确保你没有在你的Http工厂中设置globalHeaders。

我已经成功地使用了下面的工具。我和primeNg没有利害关系，只是传递我的建议。

http://www.primefaces.org/primeng/#/fileupload

Angular 2对上传文件提供了很好的支持。不需要第三方库。

<input type="file" (change)="fileChange($event)" placeholder="Upload file" accept=".pdf,.doc,.docx">

fileChange(event) {
    let fileList: FileList = event.target.files;
    if(fileList.length > 0) {
        let file: File = fileList[0];
        let formData:FormData = new FormData();
        formData.append('uploadFile', file, file.name);
        let headers = new Headers();
        /** In Angular 5, including the header Content-Type can invalidate your request */
        headers.append('Content-Type', 'multipart/form-data');
        headers.append('Accept', 'application/json');
        let options = new RequestOptions({ headers: headers });
        this.http.post(`${this.apiEndPoint}`, formData, options)
            .map(res => res.json())
            .catch(error => Observable.throw(error))
            .subscribe(
                data => console.log('success'),
                error => console.log(error)
            )
    }
}

使用@angular/core": "~2.0.0"和@angular/http: "~2.0.0"

这是一个有用的教程，如何使用ng2-file-upload和不使用ng2-file-upload上传文件。

对我来说很有帮助。

目前，教程包含几个错误:

1-客户端应具有与服务器相同的上传url 在app.component.ts中更改行

const URL = 'http://localhost:8000/api/upload';

to

const URL = 'http://localhost:3000';

2-服务器发送响应为'text/html'，所以在app.component.ts更改

.post(URL, formData).map((res:Response) => res.json()).subscribe(
  //map the success function and alert the response
  (success) => {
    alert(success._body);
  },
  (error) => alert(error))

来

.post(URL, formData)  
.subscribe((success) => alert('success'), (error) => alert(error));

上传带有表单字段的图像

SaveFileWithData(article: ArticleModel,picture:File): Observable<ArticleModel> 
{

    let headers = new Headers();
    // headers.append('Content-Type', 'multipart/form-data');
    // headers.append('Accept', 'application/json');

let requestoptions = new RequestOptions({
  method: RequestMethod.Post,
  headers:headers
    });



let formData: FormData = new FormData();
if (picture != null || picture != undefined) {
  formData.append('files', picture, picture.name);
}
 formData.append("article",JSON.stringify(article));

return this.http.post("url",formData,requestoptions)
  .map((response: Response) => response.json() as ArticleModel);
} 

在我的情况下，我需要。net Web Api在c#

// POST: api/Articles
[ResponseType(typeof(Article))]
public async Task<IHttpActionResult> PostArticle()
{
    Article article = null;
    try
    {

        HttpPostedFile postedFile = null;
        var httpRequest = HttpContext.Current.Request;

        if (httpRequest.Files.Count == 1)
        {
            postedFile = httpRequest.Files[0];
            var filePath = HttpContext.Current.Server.MapPath("~/" + postedFile.FileName);
            postedFile.SaveAs(filePath);
        }
        var json = httpRequest.Form["article"];
         article = JsonConvert.DeserializeObject <Article>(json);

        if (!ModelState.IsValid)
        {
            return BadRequest(ModelState);
        }

        article.CreatedDate = DateTime.Now;
        article.CreatedBy = "Abbas";

        db.articles.Add(article);
        await db.SaveChangesAsync();
    }
    catch (Exception ex)
    {
        int a = 0;
    }
    return CreatedAtRoute("DefaultApi", new { id = article.Id }, article);
}

在Angular 2+中，让Content-Type为空是非常重要的。如果您将“内容类型”设置为“multipart/form-data”，则上传将无法工作!

upload.component.html

<input type="file" (change)="fileChange($event)" name="file" />

upload.component.ts

export class UploadComponent implements OnInit {
    constructor(public http: Http) {}

    fileChange(event): void {
        const fileList: FileList = event.target.files;
        if (fileList.length > 0) {
            const file = fileList[0];

            const formData = new FormData();
            formData.append('file', file, file.name);

            const headers = new Headers();
            // It is very important to leave the Content-Type empty
            // do not use headers.append('Content-Type', 'multipart/form-data');
            headers.append('Authorization', 'Bearer ' + 'eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9....');
            const options = new RequestOptions({headers: headers});

            this.http.post('https://api.mysite.com/uploadfile', formData, options)
                 .map(res => res.json())
                 .catch(error => Observable.throw(error))
                 .subscribe(
                     data => console.log('success'),
                     error => console.log(error)
                 );
        }
    }
}