jQuery-$ .when延迟对象数组的语法 [英] JQuery - $.when syntax for array of Deferred objects

问题描述

这是我第一次使用$.when，语法有困难.
我的代码类似于下面的简化示例.它可以工作(如果我简化时没有引起错误). 我的问题是我不知道customerIds数组将包含的许多元素.

It is the first time I am using $.when and I am having difficulty with the syntax.
I have code similar to simplified example below. It works (if I haven't caused an error when I simplified it). My problem is that I don't know home many elements the customerIds array would contain.

var customerIds = new [1, 2, 3];

$.when(
    getCustomerData(customerIds[0]),
    getCustomerData(customerIds[1]),
    getCustomerData(customerIds[2])
).then(function() {
    alert('success');
}).fail(function() {
    alert('error');
});

function getCustomerData(int id) {
    return new $.Deferred(function(defer) {
                    doSomeWork(id, defer);
    }).promise();       
}

我想按如下方式编写$.when语句，但是很难正确使用语法.

I would like to write the $.when statement as follows but having difficulty getting the syntax right.

$.when(
    getCustomerDataCalls(customerIds),
).then(function() {
    alert('success');
}).fail(function() {
    alert('error');
});

getCustomerDataCalls的实现方式为:

function getCustomerDataCalls(customerIds) {
    var dfds = [];

    for (var id in customerIds) {
        dfds.push(new $.Deferred(function(defer) {
                                    doSomeWork(id, defer);
                                 }).promise());     
    }

    return dfds;
}

不幸的是，我的实现出现了问题，我无法弄清哪里出了问题.我最好的猜测是返回Deferred s

Unfortunately something is wrong with my implementation and I cannot work out where I am going wrong. My best guess is that something is going wrong when returning an array of Deferreds

更新:
在lanzz提到我的人为例子已经返回Deferred之后，我更新了代码，更新了我的例子以包含doSomeWork

Update:
I updated the code after lanzz mentioned that my contrived example already returns a Deferred, I updated my example to include doSomeWork

推荐答案

是的，我也偶然发现了这一点:when不允许轻易地传递数组.但是您可以使用apply达到所需的结果.

Yes, I have stumbled upon this as well: when does not easily allow to be passed an array. But you could use apply to achieve the desired result.

$.when.apply($, getCustomerDataCalls(customerIds))

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