LINQ to Entities无法识别方法'System.Windows.Forms.DataGridViewCell get_Item（Int32）'方法

Question

嗨我太新的实体框架和即时通讯使用它在Windows窗体应用程序。

  using (GezentiEntities GE = new GezentiEntities()) 
     { 
      var cities = from c in GE.Cities 
         where c.CountryId == ((Guid)(dgCountry.SelectedRows[0].Cells[0].Value)) 
         select new { c.Id, Şehir = c.Name }; 
      dgCity.DataSource = cities.ToList(); 

     } 

on dgCity.DataSource = cities.ToList（）;当它使用条件和（（Guid）（dgCountry.SelectedRows [0] .Cells [0] .Value））代码工作正常它给我的ID时，它给了我错误。

Answer 1

您可以尝试获得所需的ID了LINQ到实体查询

var id = (Guid)dgCountry.SelectedRows[0].Cells[0].Value; 
var cities = from c in GE.Cities 
         where c.CountryId == id 
         select new { c.Id, Şehir = c.Name }; 
      dgCity.DataSource = cities.ToList();