Textarea with Character Limit

Introduction

In this lab, we will be building a limited textarea component using React. The purpose of this lab is to provide a hands-on experience in utilizing React hooks, such as useState() and useCallback(), to create a component that limits the number of characters a user can input in a textarea. By the end of this lab, you will have a functional textarea component that displays the character count and limits the number of characters a user can input.

Textarea With Character Limit

index.html and script.js have already been provided in the VM. In general, you only need to add code to script.js and style.css.

Here's the code:

const LimitedTextarea = ({ rows, cols, value, limit }) => {
  const [content, setContent] = React.useState(value.slice(0, limit));

  const setFormattedContent = React.useCallback(
    (text) => {
      setContent(text.slice(0, limit));
    },
    [limit]
  );

  return (
    <>
      <textarea
        rows={rows}
        cols={cols}
        onChange={(event) => setFormattedContent(event.target.value)}
        value={content}
      />
      <p>
        {content.length}/{limit}
      </p>
    </>
  );
};

ReactDOM.createRoot(document.getElementById("root")).render(
  <LimitedTextarea limit={32} value="Hello!" />
);

In this code, we:

• Simplified the comments to provide a more concise overview of what each part of the code does.
• Removed unnecessary code comments.
• Removed the setContent function from the useCallback dependency array, as it doesn't need to be there.
• Added parentheses around the text argument in the useCallback function for consistency.
• Used arrow functions for the onChange event handler for brevity.

Please click on 'Go Live' in the bottom right corner to run the web service on port 8080. Then, you can refresh the Web 8080 Tab to preview the web page.

Summary

Congratulations! You have completed the Textarea With Character Limit lab. You can practice more labs in LabEx to improve your skills.