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javascripthtmlweb-componentcustom-element

Custom HTML element that behaves like the built-in <div> elment

I want to create a custom HTML element that behaves exactly like the built-in <div> element. I'm trying to prevent a <div> soup. I would for example want to have a <currency-list> element. This element should behave exactly like the <div> element. The only difference is the name. How can I achieve this?

Thanks, Yosemite

Solution

  • a DIV (HTMLDivElement) is a block element.

    But you don't even need a defined Custom Element/Web Component to make a block element

    customElements.define("currency-list", class extends HTMLElement {
  connectedCallback() {
    this.style.display = "block";
  }
});
    another-list {
  display: block;
}

body>*:defined {
  background: green;
  color: beige;
}

body>*:not(:defined) {
  background: lightgreen;
}
    Line 1
<currency-list>Hello Web Component</currency-list>
Line 3
<div>Line 4</div>
Line 5
<another-list onclick="alert(this.constructor.name)">Line 6</another-list>
Line 7

    Notes:

    • <another-list> is an HTMLUnknownElement; nothing wrong with using it, its constructor is an HTMLElement, so can do everything an HTMLElement can do.
      For more on the value of Unknown Elements see my Dev.to post

    • You can set any CSS display value on a DIV, you can't on your own Elements, as it will destroy the display:block setting.

    PS. tag your SO questions web-component and/or custom-element