类型“ HTMLElement”上不存在属性“ pseudoStyle”

Question

I'm trying to modify the pseudo element's height using Typescript.

I'm getting the following error in my IDE (vscode)

This is my code.

// select element
let el: HTMLElement = document.getElementById('filter-container');
//  style the height of psydo element
el.pseudoStyle("before", "height", newHeight);
...

Answer 1

You can't style a pseudo-class on a particular element alone, you can do it by altering the stylesheet:

document.styleSheets[0].insertRule('#id:hover { background-color: blue; }', 0);
document.styleSheets[0].cssRules[0].style.backgroundColor= 'blue';

Answer 2

尝试el.prototype.pseudoStyle("before", "height", newHeight);

Answer 3

As I know in JavaScript we can't change pseudo elements and I guess same in TS because of it is a JS superset. With best regards.