有没有一种简单的方法来返回成功调用$ q.all而无需创建一个$ q.defer（）的变量？ [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（做$ HTTP调用）方法。在
控制器我有code是这样的：

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) {

虽然我没有必要等待在syncMethod1（）我把这个$ q.all内让事情变得简单，让我
更改为异步如果我将来想要的方式。

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.

有关的同步功能，我称他们是这样的：

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;
};

我想知道什么是，如果有，我可以有同步的方法返回$ q.all数据，但如果没有了我
需要创建一个延迟变量，然后做defer.promise的回报？只是试图让同步方法那样简单
越好。

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，采取纯值，以及不仅承诺（它会自动将其转换）。您的同步方法应该只是做

$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（可以在真正的同步环境中使用也一样）。

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

我怎样才能从一个值承诺不使用繁琐的deferreds？

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

您可以使用 $ q.when ：

You can use $q.when:

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

如果值是不是已经承诺，则承诺将返回一个与价值尽快解决。请注意，这必然在code介绍异步，所以它不是一个真正的 syncMethod 了。

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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