有没有办法简化这个linq

Question

我有2个bool标志,需要相应地过滤我的集合.必须有一个更清洁的方法来做到这一点.如果有人能指出我正确的方向,我会很感激.谢谢.

var _filteredEvents = from ev in _events 
                      select ev;
if (!queueEmail) // don't queue email
{
    if (!queueTextMessaging) // don't queue textmessaging
    {
        _filteredEvents = from ev in _events
                              where ev.QueueTypeEnumText != QueueType.TextMessage.ToString() 
                                && ev.QueueTypeEnumText !=QueueType.Email.ToString()
                              select ev;
    }
    else
    {
         _filteredEvents = from ev in _events
                              where ev.QueueTypeEnumText != QueueType.Email.ToString()
                              select ev;
    }
}
else //queue email
{
    if (!queueTextMessaging) //don't queue textmessaging
    {
        _filteredEvents = from ev in _events
                          where ev.QueueTypeEnumText != QueueType.TextMessage.ToString()
                          select ev;
    }
}

Answer 1

由于LINQ使用延迟执行,您只需将Where()扩展名更改为对象,然后随意重新分配:

var _filteredEvents = _events; 
if (!queueEmail)
     _filteredEvents =  _filteredEvents.Where(ev => ev.QueueTypeEnumText != QueueType.Email.ToString());
if (!queueTextMessaging)
     _filteredEvents =  _filteredEvents.Where(ev => ev.QueueTypeEnumText != QueueType.TextMessage.ToString());