React Js Convert Positive Number to Negative

React Js Convert Positive Number to Negative:In ReactJS, converting a positive number to a negative one can be achieved in two ways. Firstly, by using the setState method to create a function that toggles the sign of a state variable, effectively converting it to a negative number. Alternatively, you can utilize the Math.abs() function to ensure the number is positive before negating it, achieving the same result. Both methods involve updating the component's state to reflect the desired conversion from positive to negative

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How can you convert a positive number to a negative number using Reactjs?

This React.js code snippet creates a simple web application that converts a positive number to its negative counterpart. It uses React's useState hook to manage input and output states. Users enter a number in an input field, click the "Convert" button, and the app validates and converts the input. It checks for empty or invalid inputs and displays appropriate messages. If a valid number is entered, it calculates and displays its negative value. The app provides real-time feedback to users and demonstrates the core concepts of React, including state management and event handling.

React Js Convert Positive Number to Negative Example

  <script type="text/babel">
    const { useState } = React;
    function App() {
      const [inputNumber, setInputNumber] = useState('123');
      const [convertedNumber, setConvertedNumber] = useState('');

      const convertNumber = () => {
        if (inputNumber === '') {
          setConvertedNumber('Please enter a number.');
        } else {
          const number = parseFloat(inputNumber);
          if (isNaN(number)) {
            setConvertedNumber('Invalid input. Please enter a valid number.');
          } else {
            const converted = -number;
            setConvertedNumber(`Converted number: ${converted}`);
          }
        }
      };

      return (
        <div className='container'>
          <h3 className='title'>React Js Convert Positive to Negative Number</h3>
          <input
            type="text"
            className='input-field'
            placeholder="Enter a number"
            value={inputNumber}
            onChange={(e) => setInputNumber(e.target.value)}
          />
          <button className='convert-button' onClick={convertNumber}>Convert</button>
          <p className='converted-number'>{convertedNumber}</p>
        </div>

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

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Output of React Js Convert Positive Number to Negative

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How can you use the `Math.abs` function in Reactjs to convert a positive to its negative equivalent?

This React.js code snippet initializes a component called "App" that uses state variables to manage a positive number and its corresponding negative counterpart. When the "Convert to Negative" button is clicked, the convertToNegative function is called. It calculates the negative number by applying the -Math.abs() method to the positive number, effectively changing its sign. The result is stored in the negativeNumber state variable using setNegativeNumber, which causes the component to re-render, displaying both the positive and negative numbers. This simple application demonstrates how React can dynamically manipulate and display data based on user interactions.

React Js Convert Positive Number to Negative using Math.abs Example

  <script type="text/babel">
    const { useState } = React;
    function App() {
      const [positiveNumber, setPositiveNumber] = useState(42);
      const [negativeNumber, setNegativeNumber] = useState();

      const convertToNegative = () => {
        const newNegativeNumber = -Math.abs(positiveNumber);
        setNegativeNumber(newNegativeNumber);
      };
      return (
        <div className='container'>
          <h3>React Js Convert Positive to Negative Number</h3>
          <p className='positive-number'>Positive Number: {positiveNumber}</p>
          <p className='negative-number'>Negative Number: {negativeNumber}</p>
          <button className='convert-button' onClick={convertToNegative}>Convert to Negative</button>
        </div>
      );
    }
    ReactDOM.render(<App />, document.getElementById("app"));
  </script>

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Output of React Js Positive to Negative Number