/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

0 vote204 views1 answer
Sell html templates
Html
0 vote201 views1 answer
Negrita htm
Html
1 vote209 views3 answers
Html heading tag
Html
0 vote206 views1 answer
Twig last
Html
2 votes196 views1 answer
Python request get html code
Html
0 vote189 views4 answers
<script> var x = 4; var y = 5; var z = x + y; z = x*y; document.getElementById('demo').innerHtml= z; system.print(z); </script>
Html
49 votes196 views6 answers
How to increase font size in html
Html
25 votes223 views10 answers
Bootstrap
Html
1 vote192 views1 answer
Write python code in html
Html
0 vote185 views1 answer
Detailed list html
Html