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splice method in javascript

The splice() method in JavaScript is a powerful array method used to change the contents of an array by removing, replacing, or adding elements at a specified position. It directly modifies the original array and returns an array containing the removed elements (if any). 
Syntax:
JavaScript
array.splice(startIndex, deleteCount, item1, item2, ..., itemN);
Parameters:
  • startIndex (Required): 
    The index at which to start changing the array.
    • If startIndex is negative, it's treated as an offset from the end of the array (e.g., -1 refers to the last element).

  • If startIndex is greater than the array's length, it's treated as the array's length.
deleteCount (Optional): 
The number of elements to remove from the array, starting from startIndex. 
If deleteCount is 0, no elements are removed.
If deleteCount is omitted or greater than the number of elements remaining after startIndex, all elements from startIndex to the end of the array are removed.
item1, item2, ..., itemN (Optional): 
The elements to add to the array, starting from startIndex, after any elements have been removed.
Return Value:
The splice() method returns an array containing the removed elements. If no elements are removed, it returns an empty array. 
Common Use Cases:
removing elements.
JavaScript
    const months = ['Jan', 'March', 'April', 'June'];
    months.splice(1, 2); // Removes 2 elements starting from index 1 ('March', 'April')
    // months is now ['Jan', 'June']
adding elements.
JavaScript
    const fruits = ['apple', 'banana', 'cherry'];
    fruits.splice(2, 0, 'grape', 'lemon'); // At index 2, remove 0 elements, then add 'grape' and 'lemon'
    // fruits is now ['apple', 'banana', 'grape', 'lemon', 'cherry']
replacing elements.
JavaScript
    const colors = ['red', 'green', 'blue'];
    colors.splice(1, 1, 'yellow'); // At index 1, remove 1 element ('green'), then add 'yellow'
    // colors is now ['red', 'yellow', 'blue']
Important Note: The splice() method modifies the original array directly. If you need to manipulate a portion of an array without changing the original, consider using the slice() method instead, which returns a new array with the selected elements
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