LINQ LEFT JOIN where子句不起作用

本文介绍了LINQ LEFT JOIN where子句不起作用的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我需要返回所有事件的列表以及用户可能为某个事件所拥有的任何rsvps.但是，无论我传递的用户名是什么，它都会返回每个rsvp.我的linq查询->

I need to return a list of all the events and any rsvps a user may have for an event. However, regardless of the username I pass, It returns every single rsvp. My linq Query ->

   return (from events in this._context.Context.Events
           join rsvps in (this._context.Context.RSVPs
                          .Where(o=> o.UserName == userName))
           on events equals rsvps.Event into re
           from rsvps in re.DefaultIfEmpty()
           select events);

关系是
Events.EventID = RSVPs.EventID

Relationship is
Events.EventID = RSVPs.EventID

推荐答案

from e in _context.Context.Events
join r in _context.Context.RSVPs.Where(o => o.UserName == userName)
    on e.EventID equals r.EventID into g
select new {
    Event = e,
    Rsvps = g
};

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