是否有一种简单的方法可以将成功调用返回到 $q.all 而无需创建 $q.defer() 变量? [英] Is there an easy way to return a success call to $q.all without having to create a $q.defer() variable?

问题描述

我的应用程序有许多同步和异步(执行 $http 调用)方法.在控制器我有这样的代码:

My application has a number of synchronous and asynchronous (doing a $http call) methods. In the controllers I have code like this:

$q.all([
    asyncMethod1(),
    syncMethod1()
])
.then(function (results) {

即使我不需要等待 syncMethod1() 我把它放在 $q.all 中以保持简单并允许我如果将来需要，请将方法更改为异步.

Even though I have no need to wait on the syncMethod1() I put this inside the $q.all to keep things simple and to allow me to change the method to async if I wanted in the future.

对于同步功能，我这样称呼它们:

For the sync functions I am calling them like this:

var syncMethod1 = function () {
    var defer = $q.defer();
    var abc = 99;
    defer.resolve({
        data1: abc,
        data2: 123
    });
    return defer.promise;
};

我想知道的是，是否有一种方法可以让同步方法返回 $q.all 数据，但没有我的需要创建一个 defer 变量然后返回 defer.promise 吗?只是试图使同步方法变得简单尽可能.

What I would like to know is if there's a way that I can have the sync method return to the $q.all the data but without my needing to create a defer variable and then do a return of the defer.promise? Just trying to make the sync method as simple as possible.

推荐答案

$q.all 可以，即使没有记录，也可以采用普通值，而不仅仅是承诺(它会自动转换它们).您的同步方法应该可以

$q.all can, even if not documented, take plain values as well and not only promises (it will automatically convert them). Your sync method should just do

return {
    data1: 99,
    data2: 123
};

这是最简单的事情(也可以在真正同步的上下文中使用).

which is the most simplest thing (and can be used in really synchronous contexts as well).

如何在不使用繁琐的延迟的情况下从一个值做出承诺?

How can I make a promise from a value without using tedious deferreds?

您可以使用$q.when:

return $q.when({
    data1: 99,
    data2: 123
});

如果该值还不是一个promise，则将返回一个promise，并尽快使用该值解析.请注意，这必然会在您的代码中引入异步，因此它不再是真正的 syncMethod.

If the value is not already a promise, then a promise will be returned that is resolved with the value as soon as possible. Notice that this will necessarily introduce asynchrony in your code, so it's not really a syncMethod any more.

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