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                # Auto Resize a `<textarea>` with a Web Component

**There’s another way to do this: extend custom elements! [See this codepend](**

First, a regular `<textarea>`.

<textarea>Will NOT auto resize.</textarea>

Now a web component that wraps a `<textarea>` so that it auto resizes on input.

  <textarea>Will auto resize.</textarea>

Leveraging a `<textarea>` as a child means things fail gracefully if JavaScript isn’t present. Plus, you can still use the inner `<textarea>` to attach any attributes that are supported natively in HTML.

  <textarea rows="5" onclick="console.log('this fired')">Default value here with the attribute `rows="5" and an `onclick` event handler.</textarea>

What if you don’t add a child `<textarea>` to the web component? It won’t work. Note that nothing displays under here.



                textarea {
  display: block;
  margin: 20px 0;
  width: 400px;


                import autosize from "";

class TextareaAutosize extends HTMLElement {
  connectedCallback() {
    let textarea = this.querySelector("textarea");
    if (textarea) {
    } else {
      console.error("<textarea-autosize> requires a child <textarea>.");
customElements.define('textarea-autosize', TextareaAutosize);