如何在 JavaScript 中實現動態回調參數 (How can I achieve dynamic callback arguments in JavaScript)

問題描述

如何在 JavaScript 中實現動態回調參數 (How can I achieve dynamic callback arguments in JavaScript)

如何在 JavaScript 中實現動態回調參數

我要編寫三個函數。我為什麼這樣做是因為我想封裝 initDB 的細節，這樣我可以寫更少的代碼。下面是它的樣子：

const initDB = (schemas: any[]) =>
  Realm.open({ path: 'CircleYY.realm', schema: schemas })
    .then((realm: Realm) => ({ realm }))
    .catch((error: Error) => ({ error }));

所以基本上這個函數只是初始化一個數據庫，它會返回一個數據庫實例或一個錯誤。

我還有一些特定的數據庫寫入函數，比如下面這個：

// Delete a message
const deleteOrder = (orderID: string, realm: Realm) => {
  realm.write(() => {
    const order = realm.objects('Orders').filtered(`primaryKey = ${id}`);
    realm.delete(order);
  });
};

我下面有這三個函數：

makeDBTransaction(deleteOrder(id));

and

makeDBTransaction(writeCommentInOrder(orderId, comment))

和

const makeDBTransaction = async (callback: Function) => {
  const { error, realm } = (await initDB([
    OrderSchema,
    ProductSchema,
  ])) as InitRealm;
  if (error) return { error };
  callback(realm); // Pass realm while maintaining the arguments specified in the callback which is dynamic
  return realm.close();
};

參考解法

方法 1:

I think you can keep adding arguments in an array in a required order and then apply the arguments to the function and call that function.

//for example

function foo1(x, y) {
  console.log(x,y);
}

function foo2(cb, y) {
  const x = 3;
  cb.apply(null, [x,y]);
}

foo2(foo1, 5);

//So your code will be like this
makeDBTransaction(deleteOrder, [id]);

const makeDBTransaction = async (callback: Function, arg: any[]) => {
  const { error, realm } = (await initDB([
    OrderSchema,
    ProductSchema,
  ])) as InitRealm;
  if (error) return { error };
  arg.push(realm);
  callback.apply(null, arg);
  return realm.close();
};

(by joyce、markadm)

參考文件

1. How can I achieve dynamic callback arguments in JavaScript (CC BY‑SA 2.5/3.0/4.0)