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StudentDataContext sdc = new StudentDataContext();
/// <summary>
/// 查询某些字段至List集合
/// </summary>
public List<STUDENT> GetList()
{
var q = from s in sdc.STUDENT
select new STUDENT{SSEX= s.SSEX,SNAME= s.SNAME};
return q.ToList();
}
public static List<Item> GetItemsForListing(int ownerId)
{
ItemDataContext dataContext = new ItemDataContext();
var query = from item in dataContext.Items
where item.UserID == ownerId
orderby item.CreateTime descending
select new
{
ItemID = item.ItemID,
Title = item.Title,
CreateTime = item.CreateTime,
UserID = item.UserID
};
using (dataContext.Connection)
{
return dataContext.ExecuteQuery<Item>(query);
}
}
public static class DataContextExtensions
{
public static List<T> ExecuteQuery<T>(this DataContext dataContext, IQueryable query)
{
DbCommand command = dataContext.GetCommand(query);
dataContext.OpenConnection();
using (DbDataReader reader = command.ExecuteReader())
{
return dataContext.Translate<T>(reader).ToList();
}
}
private static void OpenConnection(this DataContext dataContext)
{
if (dataContext.Connection.State == ConnectionState.Closed)
{
dataContext.Connection.Open();
}
}
}