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To insert a style tag in a React component, wrap our css in a template string in a style tag. The expression between the curly braces will be evaluated and the style will be added....

Use the useEffect hook to listen to state changes in React. We can add the state variable we want to track to the hook's dependencies array, and the logic in the useEffect hook will run every time the state variable changes....

To get the height and width of the parent in React: Set the ref attribute on the element. In the useEffect hook, update the state variables for height and width. Use the offsetHeight and offsetWidth properties to get the height and width of the elemen...

To get the value of an input field in React: Declare a state variable that tracks the value of the input field. Add an onChange attribute to the input field. Use event.target.value to get the value of the input field and update the state variable....

Rendering nested arrays using map(): Use the map() method to iterate over the outer array. In each iteration, call the map() method of the nested array. Render the elements of the nested array....

Get input values ​​on form submission in React: Store the value of the input field in a state variable. Set the onSubmit attribute on the form element. Access the value of the input field in our handleSubmit function....

To add a class to the body element in React: Access the body element as document.body in a useEffect or event handler. Use the classList.add() method to add a class to the body tag. For example, document.body.classList.add('my-class'...

To clear the value of an input field in React: Store the value of the input in a state variable. When an event occurs, set the state variable to an empty string. For uncontrolled components, set the value of the ref to an empty string, e.g. ref.curren...

To remove a key from a React state object: Use the useState hook to store the state object. Destructure the key and remaining properties of the object. Set the state to the remaining properties....

To replace an object in an array in React state: Use the map() method to iterate over the array. In each iteration, check if a certain condition is met. Replace the objects that meet the condition and return all other objects as is....

Use the useEffect hook to call a function only once in React. When the useEffect hook is passed an empty dependencies array, it runs only when the component mounts. This is the preferred approach when we have to fetch data when the component mounts....

Use the useEffect hook to run react hooks when the component is unmounted. The function we return from the useEffect hook is called when the component is unmounted and can be used for cleanup purposes....

Using map() method with index in React: Call map() method on array. The function passed to map() method will be called with element and index....

To set an onClick listener on a link in React: Set the onClick property on the link. Every time the link is clicked, the function we passed to the props will be called....

To remove an object from the state array in React: Use the filter() method to iterate over the array. In each iteration, check if the condition is met. Set the state to the new array returned by the filter method....