在Angular中下载文件时无法获取进度和文件

本文介绍了在Angular中下载文件时无法获取进度和文件的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我有一个Angular应用程序，我只想下载一个文件.

I have an Angular application where I just want to download a file.

到目前为止，这是我的代码:

Up until now, this was my code:

this.fileNavigationService.downloadFile(element).subscribe(result => { this.generateDownload(result); });

我的服务

downloadFile(file: FileElement) { return this.http.get(this.apiUrl + '/downloadFile', { params: file.name, responseType: 'blob' }); }

现在，我想在下载文件时显示进度.在网上查找后，我发现了一些非常有用的东西.我的服务现在看起来像这样:

Now, I wanted to show the progression when I download a file. After looking up online, I came across something quite useful. My service now looks like this:

downloadFile(file: FileElement) { const req = new HttpRequest('GET', '/downloadFile?path=' + file.name, { reportProgress: true, }); return this.http.request(req).subscribe(event => { if (event.type === HttpEventType.DownloadProgress) { const percentDone = Math.round(100 * event.loaded / event.total); console.log(`File is ${percentDone}% downloaded.`); } else if (event instanceof HttpResponse) { console.log('File is completely downloaded!'); } }); }

我可以在控制台中清楚地看到进度，但是，现在有两个问题:

I can clearly see in my console the progress, however, I have now 2 problems:

• 即使下载似乎已达到100％，我的代码也永远不会进入最后一个 if
• 我的组件中的代码显然在订阅方法上被破坏了

• My code never goes into the last if even though the download appears to reach 100%
• The code in my component is obviously broken on the subscribe method

预订"类型上不存在预订"属性.

Property 'subscribe' does not exist on type 'Subscription'.

但是我似乎找不到找到使之可行的方法，因此我可以获取进度和结果文件.

But I can't seem to find a way to make this works so I can get the progression and my result file.

您有什么想法或例子可以帮助我吗?谢谢.

Do you have any idea or examples to help me on this? Thanks.

推荐答案

经过研究，终于有了此答案，我终于设法解决了我的问题.

现在这是我的服务代码:

This is now my service code:

downloadFile(file: FileElement) { return this.http.get( this.apiUrl + '/downloadFile', { params: file.name, responseType: 'blob', reportProgress: true, observe: 'events', headers: new HttpHeaders({ 'Content-Type': 'application/json' }) } ); }

在我的组件中:

this.fileNavigationService.downloadFile(element).subscribe(result => { if (result.type === HttpEventType.DownloadProgress) { const percentDone = Math.round(100 * result.loaded / result.total); console.log(percentDone); } if (result.type === HttpEventType.Response) { this.generateDownload(result.body); } });