路过的功能阵列并行异步 [英] passing arrays of functions to async parallel

问题描述

我要的功能的数组传递给node.js中的 async.js 模块< BR>
从文档以正常的方式将是：

i have to pass an array of functions to the async.js module for node.js.
the normal way from the docs would be:

async.parallel([
    function(callback){
        setTimeout(function(){
            callback(null, 'one');
        }, 200);
    },
    function(callback){
        setTimeout(function(){
            callback(null, 'two');
        }, 100);
    },
],
// optional callback
function(err, results){
});

我想这样的：

            for(var i = 0; i < jsonData.length; i++)
            {
                ...
                o.url = serviceurl;
                o.title = jsonData[i];
                var ff = function(callback){
                    obj.loadService(o.title,o.url,callback);
                }
               callItems.push(ff(function(){return true;}));
            }

            async.parallel(
            callItems,
                // optional callback
                function(err, results){
                    console.log('all calls called without any errors');
                });

贯穿始终，但主被叫回调心不是。

所以我不能说，如果所有的并行调用完成。

that runs through but the main callback isnt called.
and so i cant say if all parallel calls are done.

我失去了什么吗？

推荐答案

看起来扭曲且封锁在for循环。尝试返回您目前分配给FF值的外部函数。例如：

It looks like the closures are improperly formed in the for loop. Try an external function that returns the value you're currently assigning to ff. Example:

for(var i = 0; i < jsonData.length; i++)
{
    ...
    o.url = serviceurl;
    o.title = jsonData[i];
    var ff = makeCallbackFunc(obj, o.title, o.url);
    callItems.push(ff(function () {return true;}));
}

function makeCallbackFunc(obj, title, url) {
    return function (callback) {
      obj.loadService(title, url, callback);
    };
}

我是有点要添加到callitems什么困惑 - 呼叫FF的功能参数也即结果 - 它不会是一个回调，它将执行马上

I'm a bit confused by what you are adding to callitems - namely the result of calling ff with the function parameter - it won't be a callback, it will execute right away.

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