Filter

import { useState, useMemo } from 'react';

interface MyObject {
  id: number;
  // Other properties...
}

function checkAndModifyArray(arr: MyObject[], objectToAdd: MyObject): MyObject[] {
  const index = arr.findIndex(obj => obj.id === objectToAdd.id);

  if (index !== -1) {
    // Object already exists, so remove it
    return arr.filter(obj => obj.id !== objectToAdd.id);
  } else {
    // Object does not exist, so add it
    return [...arr, objectToAdd];
  }
}

// Example usage in a functional component
function MyComponent() {
  const [myArray, setMyArray] = useState<MyObject[]>([
    { id: 1 },
    { id: 2 },
    { id: 3 }
  ]);

  const object1: MyObject = { id: 2 };
  const modifiedArray1 = useMemo(() => checkAndModifyArray(myArray, object1), [myArray]);
  setMyArray(modifiedArray1);

  const object2: MyObject = { id: 4 };
  const modifiedArray2 = useMemo(() => checkAndModifyArray(modifiedArray1, object2), [modifiedArray1]);
  setMyArray(modifiedArray2);

  // Rest of the component...
}