html2canvas not loaded when is injected as a option

[jlopezxs]

Error "html2canvas not loaded." when html2canvas is not in global but is as a option.

The error is here:

https://github.com/MrRio/jsPDF/blob/master/src/modules/html.js#L489

Proposal

Worker.prototype.isHtml2CanvasLoaded = function() {
    if (!this.opt.html2canvas || !typeof global.html2canvas !== "undefined") {
        throw new Error("html2canvas not loaded.");
    }
    return result;
};

Example:

import html2canvas from 'html2canvas';
import JsPDF from 'jspdf';

const pdf = new JsPDF({
  orientation: 'p',
  unit: 'mm',
  format: 'a4',
  compress: true,
});

pdf.html(document.body, {
      html2canvas,
      callback: (doc) => doc.save('filename.pdf'),
});

[HackbrettXXX]

You are right. This is a bug and should be fixed. Could you prepare a pull request with your proposed solution? Maybe replace !typeof global.html2canvas !== "undefined" with typeof global.html2canvas === "undefined".

[ivankoleda]

This is what I came with:

  Worker.prototype.isHtml2CanvasLoaded = function() {
    var result = typeof this.opt.html2canvas === "function"
      || typeof global.html2canvas !== "undefined";
    if (!result) {
      throw new Error("html2canvas not loaded.");
    }
    return result;
  };

this.opt.html2canvas is {} by default so I suppose check should be on typeof this.opt.html2canvas === "function". It should work, but this.opt.html2canvas seem to be initialized after the first call of isHtml2CanvasLoaded so this function still throws an error . But I struggled to dive deeper, maybe someone will find it useful.

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This issue is stale because it has been open 90 days with no activity. It will be closed soon. Please comment/reopen if this issue is still relevant.

[HackbrettXXX]

I have to revoke my initial answer. The html2canvas property in the options object is for passing options to html2canvas not for passing the html2canvas function. With #2804, the html method will now load html2canvas dynamically using the respective module format of the loaded jsPDF bundle. With that I think it is not necessary to pass html2canvas to the html method anymore.

[github-actions]

This issue is stale because it has been open 90 days with no activity. It will be closed soon. Please comment/reopen if this issue is still relevant.