类型错误：无法读取未定义的属性（读取“过滤器”）

Question

I am trying to create an event to delete elements on button click but get the error "TypeError: Cannot read properties of undefined (reading 'filter')"

const Todo = ({ text, todo, todos, setTodos }) => {
  const deleteHandler = () => {
    setTodos(todos.filter((el) => el.id !== todo.id));
  };

  return (
    <div className="todo">
      <li className="todo-item">{text}</li>
      <button className="complete-btn">
        <i className="fas fa-check"></i>
      </button>
      <button onClick={deleteHandler} className="trash-btn">
        <i className="fas fa-trash"></i>
      </button>
    </div>
  );
};

Answer 1

you have to check if element exists or not, i am hoping its array with id property, if its undefined , so no point in calling .fliter on it, it will surely throw error, call only when it have data, like this will fix the issue, i do this in my project too,

const deleteHandler = () =>{
   setTodos(todos && todos.filter((el) => el.id !== todo.id));
};

you can do this instead,

const deleteHandler = () =>{
   if(todos ){
      setTodos(todos.filter((el) => el.id !== todo.id));
   }
};