DELETE FROM ARRAYS (TODO LIST)

 FIRST WE MODIFY THE ADDTASK FUNCTION , WE ADD AN ARROW FUNCTION

DELETION CAN BE PERFORMED BY A TASK'S ID.

A DELETE BUTTON IS ADDED , ALONG THE SIDE OF TASK IN THE LIST. THE ID HAS TO BE SENT AS A PARAMETER TO THE DELETE FUNCTION.

HERE , THE ID HAS TO BE PASSED SO WE USE AN ARROW FUNCTION , IF WE DIRECTLY SEND AS <button onClick={deleteTask(task.id)}>delete</button>

HERE THE DELETE METHOD GETS EXECUTED, BUT WE DONOT WANT THAT, WE ONLY WANT THE ID PARAMETER TO BE SENT.

   <ul>
        {tasks.map((task) => (
          <li key={task.id}>
            <span>{task.task}</span>
            <button onClick={() => deleteTask(task.id)}>delete</button>
          </li>
        ))}
      </ul>

DELETE FUNCTION

TO DELETE, WE USE FILTER METHOD.


THE FILTER METHOD , FILTERS OUT THE ITEMS BASED ON THE CONDITION. 

  let deleteTask = (id) => {
    setTask((prevTask) => {
      return tasks.filter((task) => task.id != id);
    });
  };

BY SENDING THE ID AS A PARAMETER TO THE FILTER METHOD WE CAN FILTER OUT THE TASKS AND DELETE.




  let addTask = () => {
    setTask((prevTask) => {
      return [...prevTask, { task: newTask, id: uuidv4() }];
    });
    setNewTask("");
  };

  let updateChange = (event) => {
    setNewTask(event.target.value);
  };

  let deleteTask = (id) => {
    setTask((prevTask) => {
      return tasks.filter((task) => task.id != id);
    });
  };











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