C# 在c的linq查询中获取多个连接时出错

下面指定的查询显示编译时的错误。它表示wfmilestoneprojectrel的名称不在equals右侧的范围内。考虑交换等式两边的表达式。 我如何解决这个问题？ 请帮忙

var test = 
   (from wfmilestonedefinition in _context.WF_MILESTONE_DEFINITION
    join wfmilestoneprojectrel in _context.WF_MILESTONE_PROJECT_REL
        on wfmilestonedefinition.MILESTONE_ID equals wfmilestoneprojectrel.MILESTONE_ID
    join workflowrecord in _context.WORKFLOW_RECORD
        on wfmilestoneprojectrel.PROJECT_ID equals workflowrecord.PROJECT_ID
    join workflowmilestone in _context.WORKFLOW_MILESTONE
        on
        new
            {
                wfmilestoneprojectrel.MILESTONE_PROJECT_REL_ID,
                workflowrecord.WF_ID
            } equals
        new
            {
                MILESTONE_PROJECT_REL_ID = wfmilestoneprojectrel.MILESTONE_PROJECT_REL_ID,
                workflowmilestone.WF_ID
            }
    select workflowmilestone).ToList();

下面给出了运行良好的相关Sql查询： 选择dbo.WF\u里程碑\u定义.MILESTONE\u ID，dbo.WF\u里程碑\u定义.MILESTONE\u名称，dbo.WF\u里程碑\u项目\u REL.PROJECT\u ID， dbo.WORKFLOW\u RECORD.WF\u ID，dbo.WORKFLOW\u MILESTONE.MILESTONE\u E\u DATE 从dbo.WF\u里程碑\u定义内部联接 dbo.WF\u里程碑\u项目\u与dbo.WF\u里程碑\u定义相关。里程碑\u ID=dbo.WF\u里程碑\u项目\u相关。里程碑\u ID内部联接 dbo.WF\u里程碑上的dbo.WORKFLOW\u记录\u项目\u REL.PROJECT\u ID=dbo.WORKFLOW\u记录.PROJECT\u ID内部联接 dbo.WORKFLOW\u上的里程碑 dbo.WF_里程碑_项目_REL.millestone_项目_REL_ID=dbo.WF_里程碑_项目_REL.millestone_项目_REL_ID

---

dbo.WORKFLOW\u RECORD.WF\u ID=dbo.WORKFLOW\u MILESTONE.WF\u ID查看将在后台调用的联接方法的定义：

var test = 
   (from wfmilestonedefinition in _context.WF_MILESTONE_DEFINITION
    join wfmilestoneprojectrel in _context.WF_MILESTONE_PROJECT_REL
        on wfmilestonedefinition.MILESTONE_ID equals wfmilestoneprojectrel.MILESTONE_ID
    join workflowrecord in _context.WORKFLOW_RECORD
        on wfmilestoneprojectrel.PROJECT_ID equals workflowrecord.PROJECT_ID
    join workflowmilestone in _context.WORKFLOW_MILESTONE
        on
        new
            {
                wfmilestoneprojectrel.MILESTONE_PROJECT_REL_ID,
                workflowrecord.WF_ID
            } equals
        new
            {
                MILESTONE_PROJECT_REL_ID = wfmilestoneprojectrel.MILESTONE_PROJECT_REL_ID,
                workflowmilestone.WF_ID
            }
    select workflowmilestone).ToList();

Join<TOuter, TInner, TKey, TResult>(IEnumerable<TOuter>, 
                                    IEnumerable<TInner>, 
                                    Expression<Func<TOuter, TKey>>, 
                                    Expression<Func<TInner, TKey>>, 
                                    Expression<Func<TOuter, TInner, TResult>>)

为什么不写：

var test = 
   (from wfmilestonedefinition in _context.WF_MILESTONE_DEFINITION
    join wfmilestoneprojectrel in _context.WF_MILESTONE_PROJECT_REL
        on wfmilestonedefinition.MILESTONE_ID equals wfmilestoneprojectrel.MILESTONE_ID
    join workflowrecord in _context.WORKFLOW_RECORD
        on wfmilestoneprojectrel.PROJECT_ID equals workflowrecord.PROJECT_ID
    join workflowmilestone in _context.WORKFLOW_MILESTONE
        on
        new
            {
                wfmilestoneprojectrel.MILESTONE_PROJECT_REL_ID,
                workflowrecord.WF_ID
            } equals
        new
            {
                MILESTONE_PROJECT_REL_ID = wfmilestoneprojectrel.MILESTONE_PROJECT_REL_ID,
                workflowmilestone.WF_ID
            }
    select workflowmilestone).ToList();

join workflowmilestone in _context.WORKFLOW_MILESTONE
    on workflowrecord.WF_ID equals workflowmilestone.WF_ID

---

也许我误解了什么……/P>这部分考虑把“你不理解”的两边的表达交换起来吗？你试过了吗？是的我试过了。。但是不要工作。我从sql翻译了这个查询。sql查询也可以工作。鉴于OP在两个匿名对象中都使用了wfmilestoneprojectrel.MILESTONE\u PROJECT\u REL\u ID，我觉得它可以被删除……感谢@Alexey的反馈，但我需要在OnQuery的两个站点中都使用wfmilestoneprojectrel.MILESTONE\u PROJECT\u REL\u ID，因为它会根据我的需要过滤一些数据输出。如果我想要我的方式，请帮助我，然后我如何才能做到这一点？只要看一下sql查询，你就能理解。

var test = 
   (from wfmilestonedefinition in _context.WF_MILESTONE_DEFINITION
    join wfmilestoneprojectrel in _context.WF_MILESTONE_PROJECT_REL
        on wfmilestonedefinition.MILESTONE_ID equals wfmilestoneprojectrel.MILESTONE_ID
    join workflowrecord in _context.WORKFLOW_RECORD
        on wfmilestoneprojectrel.PROJECT_ID equals workflowrecord.PROJECT_ID
    join workflowmilestone in _context.WORKFLOW_MILESTONE
        on
        new
            {
                wfmilestoneprojectrel.MILESTONE_PROJECT_REL_ID,
                workflowrecord.WF_ID
            } equals
        new
            {
                MILESTONE_PROJECT_REL_ID = wfmilestoneprojectrel.MILESTONE_PROJECT_REL_ID,
                workflowmilestone.WF_ID
            }
    select workflowmilestone).ToList();