React Map example with index

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <script src="https://unpkg.com/react@17.0.2/umd/react.development.js"></script>
    <script src="https://unpkg.com/react-dom@17.0.2/umd/react-dom.development.js"></script>
    <script src="https://unpkg.com/@babel/standalone@7.14.7/babel.min.js"></script>
  </head>

<body>
    <div id="app"></div>
    <script type="text/babel">
      function App() {
        const data = [
          { id: 1, text: "Item 1" },
          { id: 2, text: "Item 2" },
          { id: 3, text: "Item 3" },
        ];

return (
          <div className="container">
            <h3>React change style of element in map</h3>
            {data.map((item) => (
              <div key={item.id} style={getStyle(item.id)}>
                <p>{item.text}</p>
              </div>
            ))}
          </div>
        );
      }

ReactDOM.render(<App />, document.getElementById("app"));
    </script>

/* Styling for the heading */
      .container h1 {
        font-size: 24px;
        text-align: center;
        margin-bottom: 20px;
      }

/* Styling for the list */
      .container ul {
        list-style: none;
        padding: 0;
        margin: 0;
      }

/* Styling for the list items */
      .container li {
        font-size: 18px;
        margin-bottom: 8px;
      }

/* Styling for odd-indexed list items (alternating background) */
      .container li:nth-child(odd) {
        background-color: #f9f9f9;
        padding: 8px;
        border-radius: 4px;
      }
    </style>
  </body>
</html>

 
<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <script src="https://unpkg.com/react@17.0.2/umd/react.development.js"></script>
    <script src="https://unpkg.com/react-dom@17.0.2/umd/react-dom.development.js"></script>
    <script src="https://unpkg.com/@babel/standalone@7.14.7/babel.min.js"></script>
  </head>
​
  <body>
    <div id="app"></div>
    <script type="text/babel">
      function App() {
        const data = [
          { id: 1, text: "Item 1" },
          { id: 2, text: "Item 2" },
          { id: 3, text: "Item 3" },
        ];
​
        const getStyle = (itemId) => {
          if (itemId === 1) {
            return { backgroundColor: "red", color: "white" };
          } else if (itemId === 2) {
            return { backgroundColor: "blue", color: "white" };
          } else {
            return { backgroundColor: "brown", color: "yellow" };
          }
        };
​
        return (
          <div className="container">
            <h3>React change style of element in map</h3>
            {data.map((item) => (
              <div key={item.id} style={getStyle(item.id)}>
                <p>{item.text}</p>
              </div>
            ))}
          </div>
        );
      }
​
      ReactDOM.render(<App />, document.getElementById("app"));
    </script>
​
    <style>
      #app {
        margin: 0 auto;
        width: 500px;
        text-align: center;
        box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.12),
          0 2px 4px 0 rgba(0, 0, 0, 0.24);
        padding: 20px;
      }
​
      /* Styling for the heading */
      .container h1 {
        font-size: 24px;
        text-align: center;
        margin-bottom: 20px;
      }
​
      /* Styling for the list */
      .container ul {
        list-style: none;
        padding: 0;
        margin: 0;
      }
​
      /* Styling for the list items */
      .container li {
        font-size: 18px;
        margin-bottom: 8px;
      }
​
      /* Styling for odd-indexed list items (alternating background) */
      .container li:nth-child(odd) {
        background-color: #f9f9f9;
        padding: 8px;
        border-radius: 4px;
      }
    </style>
  </body>
</html>
​