linq查询到List <string> </string>的语法

Question

我正在尝试做这样的事情......

public static List<string> GetAttachmentKeyList()
{
    DataClassesDataContext dc = new DataClassesDataContext();

    List<string> list = from a in dc.Attachments
        select a.Att_Key.ToString().ToList();

    return list;
}

Visual Studio正在说......

无法隐式转换类型'System.Linq.IQueryable＆gt;'到'System.Collections.Generic.List'。 存在显式转换（您是否错过了演员？）

什么是正确的语法???

Answer 1

试一试

public static List<string> GetAttachmentKeyList()
{
    DataClassesDataContext dc = new DataClassesDataContext();

    List<string> list = ( from a in dc.Attachments
                          select a.Att_Key.ToString() ).ToList();

    return list;
}

Answer 2

试试这个，

public static List<string> GetAttachmentKeyList()
{
    DataClassesDataContext dc = new DataClassesDataContext();

    return dc.Attachments.Select(a=>a.Att_Key).ToList();
}

Answer 3

我猜它会像下面那样。

       List<string> list = (from a in dc.Attachments
                             select a.Att_Key.ToString()).ToList<string>();

希望这会有所帮助!!