嵌套的async.each：“错误：已经调用了回调”

Question

我遇到了嵌套float工作的麻烦，我不知道为什么我收到错误：async.each即使我已经正确放置了我的回调。

Error: Callback was already called

任何帮助都会非常感激。

Answer 1

如果符合条件，则在循环浏览next();后再次呼叫default_shift。

 default_shift.week_days.map(function(day1) {
            default_shift2.week_days.map(function(day2) {
                if (condition)
                    next({error: 'The shifts overlap!'}); //The problem is here.
            });
});
next(); //If shifts overlap, next was already called.

解决问题的一种简单方法是添加标记，如果移位重叠，则忽略第二个。

var nextCalled = false;
default_shift.week_days.map(function(day1) {
    default_shift2.week_days.map(function(day2) {
        if (condition && !nextCalled){
            next({error: 'The shifts overlap!'});
            nextCalled = true;
        }
    });
});

if(!nextCalled)
   next();