根据GET参数从表名中选择数据

Question

ASP.NET MVC 4

实体框架：6.1.3

我尝试根据GET参数＆＃34;表单＆＃34; 从表名中选择数据。

我的控制器包含以下代码：

...

using System.Linq;

...

public ActionResult Index(string form, int? page)
{
    Type MyTable1Type, MyTable2Type;

    Dictionary<string, Type> TableType = new Dictionary<string, Type>()
    {
        { "MyTable1", MyTable1Type},
        { "MyTable2", MyTable2Type}
    };

    var query = db.Set(TableType[form]);

    var records = query.Select(x => x).Where(x => (!x.user_action.user.email.ToLower().Contains("@example.com")));

    // Pagination

    int PageIndex = page.HasValue ? page.Value : 1;
    var results = records.OrderByDescending(x => x.user_action.date_created).ToList().ToPagedList(PageIndex, PageSize);

    return View(results);
}

错误消息：

'System.Data.Entity.DbSet' does not contain a definition for 'Select' and no extension method 'Select' accepting a first argument of type 'System.Data.Entity.DbSet' could be found (are you missing a using directive or an assembly reference?)

你能帮忙吗？谢谢。 ：）