誤差在LINQ無法從 'System.Collections.Generic.IEnumerable <AnonymousType＃1>' 轉換爲「System.Linq.IQueryable <AnonymousType＃2>

Question

內含有錯誤：

error in linq cannot convert from 'System.Collections.Generic.IEnumerable' to 'System.Linq.IQueryable

爲什麼呢？

public class ListQuestionAssessor 
{ 
     public string sum { get; set; } 
     public int QuestionsID { get; set; } 
     public int AssessorID { get; set; } 
     public int AssessID { get; set; } 
} 

List<ListQuestionAssessor> objList = new List<ListQuestionAssessor>(); 

     var lisaAddAssessor = (from p in objList 
           where 
            ! 
            (from assessor in ObjNotIn 
            select new 
            { 
             assessor.id 
            }).Contains(new { p.QuestionsID }) 
           select new QuestionAssessor() 
           { 
            QuestionsID = initQuestionerId 

           }).ToList(); 

Answer 1

我要說的是，問題是，你正試圖檢查

.Contains(new { p.QuestionsID }) 

包含期待同類型集合的參數。並且由於收集是匿名的，所以這可能是導致錯誤的原因。

改寫爲

.Any(a => a.id == p.QuestionsID)