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How to render data in ReactJS textarea

Getting Started

In this blog post, we will explore how to render data in a ReactJS textarea. ReactJS, in case you're wondering, is a popular JavaScript library for building user interfaces. In this context, rendering refers to the process of displaying data on the web page. But don't worry if you're a beginner programmer, we will walk through this process step-by-step, explaining each part of the code and providing practical examples.

Understanding Textarea in ReactJS

A textarea in ReactJS (or any other web development library) is a part of the webpage where the user can input multiple lines of text. Think of it as a kind of digital notebook that users can write in.

In ReactJS, we handle the textarea slightly different compared to HTML. In HTML, textarea content is usually placed between the opening and closing tags, like this:

<textarea>Some text here...</textarea>

But in ReactJS, we place the content of the textarea inside a value attribute. It looks something like this:

<textarea value='Some text here...' />

This difference is because ReactJS uses a concept called "controlled components". These are components that get their state (i.e., their current value or condition) directly from the React state, and their changes are handled by functions within the React component. This gives us more control over the form elements and how they behave.

Rendering Data in Textarea

To render data in a textarea, we first need to create a state variable to store the data. In ReactJS, we use the useState function to do this. Here's an example:

import React, { useState } from 'react';

function App() {
  const [text, setText] = useState('');

  return (
    <div className="App">
      // Our textarea goes here
    </div>
  );
}

export default App;

In this example, we created a state variable named text, and a function named setText. The useState('') function sets the initial value of the text to an empty string.

The next step is to create the textarea and link it to the state variable. We do this by setting the value of the textarea to the state variable, and handling changes with the setText function. It looks something like this:

<textarea value={text} onChange={event => setText(event.target.value)} />

In this code, the value of the textarea is set as whatever text is stored in the state. The onChange function handles what happens when the user types into the textarea. It takes the event object as a parameter (which has information about the triggered event), accesses the value of the textarea (with event.target.value), and sets that as the new value for the text state.

Full Example

Putting it all together, here's a complete example of a ReactJS component with a textarea that renders data:

import React, { useState } from 'react';

function App() {
  const [text, setText] = useState('');

  return (
    <div className="App">
      <textarea 
        value={text} 
        onChange={event => setText(event.target.value)} 
      />
    </div>
  );
}

export default App;

In this example, whenever you type into the textarea, you're actually updating the state of the text in the App component. And because the value of the textarea is tied to this state, it will automatically display whatever is currently stored in the text state.

Conclusion

And there you have it! You now have the tools to render data in a textarea in ReactJS. Remember, the key takeaway is that in ReactJS, we use the concept of controlled components to handle form elements like textarea. By linking the textarea directly to the React state and handling changes with a function within the React component, you get to have full control over the textarea and its behavior.

As you continue your programming journey, you'll notice that this pattern of storing state and handling changes is a common one in ReactJS. It's like being a puppeteer and having the strings to control your puppet (in this case, the textarea). The more you practice it, the better you'll get at mastering this powerful tool in the ReactJS toolbox. Happy coding!