how to download a pdf file from an url in angular 5 - angular5

Question

I currently spend one day in this issue,still failed to download a file from an url in angular 5
leadGenSubmit() {
return this.http.get('http://kmmc.in/wp-content/uploads/2014/01/lesson2.pdf',
{responseType:ResponseContentType.Blob}).subscribe((data)=>{
console.log(data);
var blob = new Blob([data], {type: 'application/pdf'});
console.log(blob);
saveAs(blob, "testData.pdf");
},
err=>{
console.log(err);
}
)
}
when I run above code it shows following error
ERROR TypeError: req.responseType.toLowerCase is not a function
at Observable.eval [as _subscribe] (http.js:2187)
at Observable._trySubscribe (Observable.js:172)
how can I solve this issue.Can any one post the correct code to download a pdf file from an url in angular 5?

Answer 1

I think you should define header and responseType like this:
let headers = new HttpHeaders();
headers = headers.set('Accept', 'application/pdf');
return this.http.get(url, { headers: headers, responseType: 'blob' });

Answer 2

Here is my simple solution to open a PDF based on an ID in Angular :
In my service, I created this method :
public findById(id?: string): Observable<Blob> {
return this.httpClient.get(`${this.basePath}/document/${id}`, {responseType: 'blob'});
}
Then in my component, I can do use this method (behind a button or whatever):
showDocument(documentId: string): void {
this.yourSuperService.findById(documentId)
.subscribe((blob: Blob): void => {
const file = new Blob([blob], {type: 'application/pdf'});
const fileURL = URL.createObjectURL(file);
window.open(fileURL, '_blank', 'width=1000, height=800');
});
}

Answer 3

Try this
let headers = new HttpHeaders();
headers = headers.set('Accept', 'application/pdf');
return this.http.get(url, { headers: headers, responseType: 'blob' as 'json' });
References:
Discussion on Angular Github
Stackoverflow