为什么我的 function 在尝试将值推送到我的数组时不起作用？

Question

 const todo = [{ task: 'Wash Plates', day: 'Monday' },{ task: 'Clean Pc', day: 'Tuesday' },] let addTask = todo.push((todoTask, date) => { todo.task = todoTask, todo.day = date }) addTask('car', 'monday') for (var i = 0; i < todo.length; i++) { console.log(`${i+1}. ${todo[i].task} on ${todo[i].day}`); }

Why is the addTask not a function, even when i use normal functions (not arrows) it has the same result. The loop below is fine and so is the array above. I want to be able push values onto my todo list. Can someone help please.

Answer 1

You've got .push and the arrow function mixed up. Try this:

let addTask = (todoTask, date) => {
  todo.push({
    task: todoTask,
    day: date
  })
};

Answer 2

addTask is not a function. You're calling todo.push() with a function as the argument, then you're assigning the return value to addTask . push() returns the new length of the array, so you're adding the function to the array and then setting addTask to the array length.

You need to take the function out of the push() argument. Then you need to use correct syntax for an object literal.

 const todo = [{ task: 'Wash Plates', day: 'Monday' }, { task: 'Clean Pc', day: 'Tuesday' }, ] let addTask = (todoTask, date) => todo.push({ task: todoTask, todo: date }) addTask('car', 'monday') for (var i = 0; i < todo.length; i++) { console.log(`${i+1}. ${todo[i].task} on ${todo[i].day}`); }

Answer 3

You are pushing the following function into the end of the todo array:

(todoTask, date) => { ... }  

after which the call to Array.push returns the new length of the todo array , hence you get the length (a number) as a returned value to addTask .

The definition of addTask function should be:

let addTask = (task, day) => todo.push({task ,day});

Answer 4

Similar to the others, but you can change your variable names to allow for the ES6 object construction to be minimized.

 const todo = [{ task: 'Wash Plates', day: 'Monday' }, { task: 'Clean Pc', day: 'Tuesday' }, ] let addTask = (task, day) => todo.push({task, day}); addTask('car', 'monday') for (var i = 0; i < todo.length; i++) { console.log(`${i+1}. ${todo[i].task} on ${todo[i].day}`); }

Answer 5

The correct notation for an arrow function is this: (args) => {}. addTask is not actually in function format, it just receives the push return, to resolve this do:

let addTask = (todoTask, date) => todo.push({task: todoTask, day: date})

eg

 const todo = [{ task: 'Wash Plates', day: 'Monday' },{ task: 'Clean Pc', day: 'Tuesday' },] let addTask = (todoTask, date) => todo.push({task: todoTask, day: date}) addTask('car', 'monday') for (var i = 0; i < todo.length; i++) { console.log(`${i+1}. ${todo[i].task} on ${todo[i].day}`); }

Answer 6

you don't need a separate function do add some values to your array. Try this:

array.push({
   task: todoTask,
   day: date
})

although if you want to make a function:

const addTask = (task, day) => todo.push({task, day})