Node.js - 使用异步库 - async.foreach 与对象 [英] Node.js - Using the async lib - async.foreach with object

问题描述

我正在使用节点异步库 - https://github.com/caolan/async#forEach 并且想遍历一个对象并打印出它的索引键.完成后，我想执行回调.

I am using the node async lib - https://github.com/caolan/async#forEach and would like to iterate through an object and print out its index key. Once complete I would like execute a callback.

这是我到目前为止所拥有的，但从未见过 '迭代完成':

Here is what I have so far but the 'iterating done' is never seen:

    async.forEach(Object.keys(dataObj), function (err, callback){ 
        console.log('*****');

    }, function() {
        console.log('iterating done');
    });  

1. 为什么最终的函数没有被调用?

1. Why does the final function not get called?

如何打印对象索引键?

推荐答案

final 函数没有被调用，因为 async.forEach 要求你调用 callback 函数每个元素.

The final function does not get called because async.forEach requires that you call the callback function for every element.

使用这样的东西:

async.forEach(Object.keys(dataObj), function (item, callback){ 
    console.log(item); // print the key

    // tell async that that particular element of the iterator is done
    callback(); 

}, function(err) {
    console.log('iterating done');
});  

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