When using html2canvas in Angular, it is not possible to call an expression that does not have a call signature

I'm currently working on integrating the html2canvas library into an Angular 8 project.

Despite trying to install the html2canvas types using

npm install --save @types/html2canvas
, I'm still facing issues with its functionality.

Here's how I set up my template:

<div #myform>
  <form>
    ...
  </form>
</div>

In the component file, I have the following code:

import { Component, OnInit, ViewChild, ElementRef } from '@angular/core';
import * as html2canvas from 'html2canvas';

@Component({
  selector: 'app-pdf-viewer',
  templateUrl: './pdf-viewer.component.html',
  styleUrls: ['./pdf-viewer.component.scss']
})
export class PdfViewerComponent {
  @ViewChild('myform', { static: false, read: ElementRef }) pdfForm: ElementRef;

  constructor() {}


  pdfDownload() {
    html2canvas(this.pdfForm.nativeElement).then(canvas => {
      const imgData = canvas.toDataURL('image/png');
      document.body.appendChild(canvas);
    });
  }

}

My goal is to render the form as a canvas, but unfortunately, I keep encountering this error message:

ERROR in src/app/grid/pdf-viewer/pdf-viewer.component.ts (19,5): error TS2349: Can not invoke an expression whose type lacks a call signature. Type 'typeof import ("myroute")' you have not supported call signatures.

Answer №1

Issue resolved! Much appreciated :)

After some trial and error, here is how I managed to successfully import the necessary package:

import html2canvas from 'html2canvas';

Answer №3

Encountered a similar problem on my Angular 8 project, and I found that the best solution was to import the library using require to avoid any errors.

Check out this helpful post.

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