/Html/Property 'on' does not exist on type 'HTMLElement'.

Property 'on' does not exist on type 'HTMLElement'.

Property 'value' does not exist on type 'HTMLElement'.

document.getElementById() returns the type HTMLElement which does not contain a value property.
The subtype HTMLInputElement does however contain the value property.

So a solution is to cast the result of getElementById() to HTMLInputElement like this:

var inputValue = (<HTMLInputElement>document.getElementById(elementId)).value;
<> is the casting operator in typescript.
See TypeScript: casting HTMLElement: https://fireflysemantics.medium.com/casting-htmlelement-to-htmltextareaelement-in-typescript-f047cde4b4c3

The resulting javascript from the line above looks like this:

inputValue = (document.getElementById(elementId)).value;
i.e. containing no type information.

Source: fireflysemantics.medium.com

Property 'on' does not exist on type 'HTMLElement'.

To prevent this error you can write:

var plotDiv: any = document.getElementById('myDiv');
plotDiv.on('plotly_relayout', ...
document.getElementById('myDiv') return HTMLElement. This type doesn't contain method
on because this method is added within plotly-latest.min.js. So in order to silence
the typescript warning you can explicity say compile not to check types for plotDiv

Another way is create type definition like:

interface PlotHTMLElement extends HTMLElement  {
  on(eventName: string, handler: Function): void;
}

var plotDiv  = <PlotHTMLElement>document.getElementById('myDiv')
plotDiv.on('plotly_relayout', function() {

});

Similar codes

4 votes284 views4 answers
Email regex html pattern
Html
0 vote283 views1 answer
Symfony twig global
Html
0 vote260 views1 answer
Easyui how to make panel collapsible
Html
0 vote302 views2 answers
Href with parameters
Html
0 vote291 views1 answer
.1
Html
0 vote296 views1 answer
Android strings plural
Html
0 vote226 views1 answer
Histogram with frequency curve using seaborn
Html
0 vote304 views1 answer
How to disable tabindex
Html
38 votes285 views6 answers
Random image
Html
0 vote252 views2 answers
Vmware workstation ubuntu 19.04
Html