LINQ to SQL의 캐스트가 유효하지 않습니다.

Question

LINQ to SQL을 사용하여 잘못된 캐스트 예외가 발생했습니다.

[Table(Name = "tbl_request$")] 
public class request 
{ 
    [Column(IsPrimaryKey = true)] 
    public float requestID; 
    [Column] 
    public string moduleCode; 
    [Column] 
    public float park; 
    [Column] 
    public string requestedRoom; 
    [Column] 
    public float week; 
    [Column] 
    public float day; 
    [Column] 
    public float period; 
    [Column] 
    public float status; 
    [Column] 
    public float semester; 
    [Column] 
    public float priority; 
    [Column] 
    public float adhoc; 
    [Column] 
    public float numStudents; 
    [Column] 
    public float collectionID; 
    [Column] 
    public float roomCount; 
} 

이 해당하는 데이터베이스 테이블을

requestID float Unchecked 
moduleCode nvarchar(255) Checked 
park float Checked 
requestedRoom nvarchar(255) Checked 
week float Checked 
day float Checked 
period float Checked 
status float Checked 
semester float Checked 
priority float Checked 
adhoc float Checked 
numStudents float Checked 
collectionID float Checked 
roomCount float Checked 

모두가 나에게 잘 보이는

에 : 여기에 C#에서 내 수업입니다. 다른 제안?

Specified cast is not valid. 

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.InvalidCastException: Specified cast is not valid. 

Source Error: 

Line 12:    var bookingtable = Database.DatabaseContext.GetTable<Database.request>(); 
Line 13:    var dict = new System.Collections.Generic.Dictionary<int, System.Collections.Generic.List<Database.request>>(); 
Line 14:    foreach (var request in bookingtable) 
Line 15:    { 
Line 16:     if (dict[(int)request.collectionID] == null) 

스택 추적은 LINQ 내부 깊숙한 곳입니다.

Answer 1

DB 유형이 FLOAT이더라도 C#은 float? 대신 double?을 원했습니다.