![]() For example, to remove only one element, you can pass the number 1 like this: let months = Ĭonsole.log(months) // Remove only one element from the array You can also define how many elements you want to remove from the array by passing a second number argument known as removeCount. In the code above, the number 2 is passed to the method, which means splice() will start removing elements from index 2. The splice() method needs at least one parameter, which is the start index where the splice operation starts. You can use the splice() method to remove the day names from the months method and add it to a new array at the same time: let months = Ĭonsole.log(days) // Creating an array of days How to remove array elements with splice()įor example, suppose you have an array named months but you have some day names in the array as follows: let months = A mixed array of month and day names Let's start with removing elements from an array first. In this tutorial, you will learn how you can remove, add, or replace elements of an array using the splice() method. This method modifies the original array and returns the removed elements as a new array. It lets you change the content of your array by removing or replacing existing elements with new ones. We can therefore delete a specific element from a previously stored array in our component state by returning a new array that does not contain the designated element using array methods such as filter() or slice() along with the spread operator, and then setting this new array as the component's state using the useState setter method.The splice() method is a built-in method for JavaScript Array objects. However, since React makes use of particular hooks for interacting with state that should be immutable, we must exercise caution when utilizing these array methods to manipulate the state produced by react hooks such as useState(). Even though it does not provide any helper libraries for working with arrays, JavaScript already has a multitude of ways for handling with arrays and other types of data. React is a JavaScript user interface library that is solely responsible for the rendering of the user interface. ConclusionĪs a recap, when dealing with React and array state, we may find ourselves in a situation where we need to delete an item from the state array of a particular React component. We are retaining all the values except the element of the index. We utilize the spread operator to construct a new array from the values excluding the index's element then we set our new state. ![]() In the initial call to the slice() method, an array is returned from the beginning up to, but not comprising, the index, and then a second call yields an array from index + 1 to the end. What if we need to delete an element from any index, rather than only index zero? This may be accomplished by combining the spread operator from JavaScript with the array object's slice() method.įirst, we need to define a function with an index argument:Ĭonst removeProduct = ( index ) => We have seen how to remove the element of index zero. The array returned by the filter() method will be used as the new state. We filter the products array to delete the first member and we set the result as the new state using the callback argument of the setProductsArray() method.Ĭalling filter with a callback that checks to see whether the index is different than zero removes the first entry from the array that has been returned. We use React's useState hook to define a state array named productsArray for our products. Here we delete the element of index zero which is the first element of the array. SetProductsArray (( products ) => products. In the callback of the state setter function, we may return a new array to update a React component's state array. Let's pretend we're working with React.js and our component state is an array. We can update the state array of a React component using the callback function of the state setter method to return a new array. How to delete an item from a React component's state array will be the focus of this section. Since our component state contains an array, how may we remove one of its elements? How to delete an element from a useState Array in a React Component ![]() We must, however, exercise caution when using these array methods to manipulate the state created by react hooks such as useState, because React uses special hooks for working with state that should be immutable. ![]() No helper libraries for arrays are provided, but JavaScript already has a number of methods to work with arrays and other data types. JavaScript's React UI library is solely responsible for rendering the user interface. When we are working with React and array state, we may need to remove an item from a React component's state array. ![]()
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