React Js Check First Letter of String is Uppercase

    const { useState } = React;

    function App() {

      const [input, setInput] = useState('Font aweosme icons');

      const isFirstLetterUppercase = input.length > 0 && input[0] === input[0].toUpperCase();

​

      const showAlert = () => {

        const message = isFirstLetterUppercase

          ? 'The first letter is uppercase.'

          : 'The first letter is not uppercase.';

        alert(message);

      };

      return (

        <div className='container'>

          <h3>React Js Check First Letter Of String Is Uppercase </h3>

          <input

            className='input-field'

            type="text"

            value={input}

            onChange={(e) => setInput(e.target.value)}

            placeholder="Enter a string"

          />

          <button className='check-button' onClick={showAlert}>Check Uppercase</button>

        </div>

​

      );

    }

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

  </script>

    const { useState } = React;

    function App() {

      const str = "hello, world!"; // Replace with your string

​

      const isFirstLetterUppercase = str => {

        if (str.length === 0) {

          return false;

        }

        const firstCharCode = str.charCodeAt(0);

        return firstCharCode >= 65 && firstCharCode <= 90;

      };

​

      const capitalizeFirstLetter = str => {

        if (isFirstLetterUppercase(str)) {

          return str;

        } else {

          const firstCharCode = str.charCodeAt(0);

          const capitalizedFirstLetter = String.fromCharCode(firstCharCode - 32);

          return capitalizedFirstLetter + str.slice(1);

        }

      };

​

      const modifiedString = capitalizeFirstLetter(str);

      return (

        <div className='container'>

          <h3 className='title'> use charCodeAt() Method</h3>

          <p className='string-info'>String: {str}</p>

          <p className='uppercase-check'>Is the first letter uppercase? {isFirstLetterUppercase(str).toString()}</p>

          <p className='modified-string'>Modified String: {modifiedString}</p>

        </div>

​

      );

    }

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

</script>

    const { useState } = React;

    function App() {

      const [inputText, setInputText] = useState('');

      const isUppercase = /^[A-Z]/.test(inputText);

​

      return (

        <div className='container'>

          <input

            type="text"

            placeholder="Enter a string"

            onChange={(e) => setInputText(e.target.value)}

            className="input-element"

          />

          <p className="paragraph-element">Is the first letter uppercase? {isUppercase ? 'Yes' : 'No'}</p>

        </div>

​

      );

    }

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

  </script>