如何绕过多个然后进入猫鼬

Question

我不想以if (!isPresent) 的身份进行检查，然后执行此操作....

当我的工作完成时，他们有什么方法可以绕过所有 then

var isPresent=false;
    myPromise
            .then((employee) => {
                    if (employee) {
                        // throw 'employee already exist';
                        isPresent = true;
                        return res.data(mapper.toFullModel(employee));

                    }
                return model;
            });
            .then(model => {
                if (!isPresent) {
                    return new db.employee(model).save();
                }
            })
            .then(employee => {
                if (!isPresent) {
                    employee.token = auth.getToken(employee);
                    return employee.save();
                }
            })
            .then(employee => {
                if (!isPresent) {
                    res.data(mapper.toFullModel(employee));
                }
            })
            .catch(err => {
                res.failure(err);
            });

Answer 1

您可以重写您的承诺链，使其第二部分嵌套：

myPromise.then(employee => {
  if (employee) {
    return res.data(mapper.toFullModel(employee));
  }
  return new db.employee(model).save().then(employee => {
    employee.token = auth.getToken(employee);
    return employee.save();
  }).then(employee => {
    return res.data(mapper.toFullModel(employee));
  });
}).catch(err => {
  res.failure(err);
});