node.js - node async queue中這個callback是什么,為什么這里輸出只有5行?
問題描述
問題解答
回答1:當然咯,因為你并發量是5,但是你的queue中并沒有fork callback,所以并發量是5,沒有結束也不會調新的咯。
var async = require(’async’);var q = async.queue(function(data, callback) { console.log(data.name);// fork callback callback();}, 5);for(var i = 0; i < 10; ++i) { q.push({ name: 0 })}回答2:
var q = async.queue(function (data, callback) { console.log(data.name); callback(null)},5)
少了callback
An asynchronous function for processing a queued task, which must call its callback(err) argument when finished, with an optional error as an argument. If you want to handle errors from an inpidual task, pass a callback to q.push(). Invoked with (task, callback).
