如何将LINQ数据绑定到下拉列表

Question

此代码的最后两行无法正常工作 - 结果将从LINQ查询返回。我只是不知道如何成功绑定指定的列在结果的下拉列表的文本字段和valuefield：

protected void BindMarketCodes() 
    { 
     List<lkpMarketCode> mcodesList = new List<lkpMarketCode>(); 

     LINQOmniDataContext db = new LINQOmniDataContext(); 

     var mcodes = from p in db.lkpMarketCodes 
         orderby 0 
         select p; 

     mcodesList = mcodes.ToList<lkpMarketCode>(); 

     //bind to Country COde droplist 
     dd2.DataSource = mcodesList; 
     dd2.DataTextField = mcodesList[0].marketName; 
     dd2.DataValueField = mcodesList[0].marketCodeID.ToString(); 

    } 

Answer 1

见下酷

protected void BindMarketCodes() 
{  
    using (var dataContext = new LINQOmniDataContext()) { 
     //bind to Country COde droplist 
     dd2.DataSource = from p in dataContext.lkpMarketCodes 
      orderby p.marketName 
      select new {p.marketCodeID, p.marketName}; 
     dd2.DataTextField = "marketName"; 
     dd2.DataValueField = "marketCodeID"; 
     dd2.DataBind(); 
    } 
} 

Answer 2

protected void BindMarketCodes() 
{ 
    using(var dc = new LINQOmniDataContext()) 
    { 
     dd2.DataSource = from p in db.lkpMarketCodes 
         orderby 0 
         select new {p.marketName, p.marketCodeID }; 
     dd2.DataTextField = "marketName"; 
     dd2.DataValueField = "marketCodeID"; 
     dd2.DataBind(); 
    } 
} 

// no need to use ToList() 
// no need to use a temp list; 
// using an anonymous type will limit the columns in your resulting SQL select 
// make sure to wrap in a using block; 

Answer 3

DropDownList ddl_RouteLocation = (DropDownList)e.Row.FindControl("ddl_RouteLocation"); 

ddl_RouteLocation.DataSource = dtLocation;--(dtlocation i have return method of linq in dtlocation) 
ddl_RouteLocation.DataTextField =dtLocation.Rows[0]"LocationName"].ToString(); 
ddl_RouteLocation.DataValueField =dtLocation.Rows[0]["LocationId"].ToString(); 
ddl_RouteLocation.DataBind(); 
ddl_RouteLocation.Items.Insert(0, new ListItem("--Select--", "0"));