LINQ錯誤的簡單連接 - 聯接子句中的表達式之一的類型不正確

Question

我試圖做一個簡單的JOIN與LINQ但出現錯誤

the type of one of the expressions in the join clause is incorrect

CODE：

var select2 = from si in db.San_Imovel 
           join sic in db.San_Imovel_caracteristica  <--- ERROR 
           on si.Imovel_Id equals sic.Imovel_Id 
          where si.Credenciada_Id == credenciada_Id      
          select new 
          { 
           si.Celula_Id, 
           si.Credenciada_Id, 
           si.Imovel_Id, 
           si.NomeArquivo, 
           si.TipoDsc1, 
           si.BairroDsc1, 
           si.AreaRealPrivativa,         
           si.ValorImovel, 
           si.ValorCondominio, 
           si.ValorIPTU, 
           si.Lat2, 
           si.Lon2, 
           si.Bairro1, 
           si.NomeCidade, 
           si.Transacao_ID 
          }; 

Answer 1

如果你的屬性有long和int?類型，那麼你可以嘗試這個連接：

var select2 = from si in db.San_Imovel 
       join sic in db.San_Imovel_caracteristica 
          .Where(x => x.Imovel_Id.HasValue) 
       on si.Imovel_Id equals (long)sic.Imovel_Id.Value 
       where si.Credenciada_Id == credenciada_Id      
       select new { ... }