React Js Check Value is Integer or String

React Js Check Value is Integer or not:In React.js, you can check if a value is an integer or a string using JavaScript's typeof operator. The typeof operator returns a string indicating the type of the operand. To check if a value is an integer, you can use the Number.isInteger() method, which returns true if the value is an integer and false otherwise.

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How can I check if a value in React.js is an integer or not?

This React.js code defines a functional component called "App" that checks whether the value stored in the state variable "myNumber" is an integer or not. The initial value of "myNumber" is set to the string '4'.

The component renders a paragraph element indicating whether the value is an integer or not based on the result of the Number.isInteger() method. If the value is an integer, it displays the message "The value is an integer", otherwise, it displays "The value is not an integer".

React Js Check Value Is Integer Or String Example

   <script type="text/babel">
        const { useState } = React;

        function App() {
            const [myNumber, setMyNumber] = useState('4');
            return (
                <div className='container'>
                    <h2>React JS Check value is Number</h2>
                    {Number.isInteger(myNumber) ? (
                        <p className="integer">The value is an integer</p>
                    ) : (
                        <p className="not-integer">The value is not an integer</p>
                    )}
                </div>

            );
        }

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

Run

Output of Check Value is Integer or String

How do you use `!isNaN(inputValue)` in React.js to check if a value is a number or a string?

This React.js code snippet creates an input field where users can enter a value. The handleInputChange function updates the inputValue state with the user's input. To determine if the input is a number or string, it uses the !isNaN(inputValue) expression. If inputValue is a number, it displays "It is a number," and if it's not a number, it displays "It is not a number." The result is shown below the input field and updates dynamically as the user types. This code demonstrates how React can be used to check and display whether the input value is a number or a string in a user-friendly manner

React Js Check Value is Number or String using !isNaN(inputValue)

  <script type="text/babel">
    const { useState } = React;
    function App() {
      const [inputValue, setInputValue] = useState('');
      const handleInputChange = (event) => {
        const value = event.target.value;
        setInputValue(value);
      }
      const isNumber = !isNaN(inputValue);
      return (
        <div className='container'>
          <h2 className='title'>React Js Check Value is Number or String</h2>
          <input
            type="text"
            className='input-field'
            placeholder="Enter a value"
            value={inputValue}
            onChange={handleInputChange}
          />
          {inputValue && (
            <p className={isNumber ? 'number-text' : 'not-number-text'}>
              {isNumber ? 'It is a number.' : 'It is not a number.'}
            </p>
          )}
        </div>

      );
    }

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

Run

Output of React Js Check Value is Number or String using !isNaN(inputValue)

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