/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

36 votes183 views6 answers
Html iframe tag
Html
0 vote180 views1 answer
Html table resize columns
Html
0 vote209 views6 answers
How to mask input in html as phone numbr
Html
0 vote190 views1 answer
Icon for right arrow
Html
0 vote174 views1 answer
How to set a var in js to be a download
Html
6 votes171 views2 answers
Html meta redirect
Html
9 votes335 views1 answer
Html floating button
Html
0 vote191 views1 answer
A open to other tab
Html
0 vote233 views1 answer
How to make a alert in powershell
Html
0 vote168 views1 answer
Select colopr bootstrap
Html