linq其中包含在IEnumerable中

Question

//\\ ---- selected items from ChechBoxList
IEnumerable<int> selSender = (from ListItem item in CheckBoxList1.Items.OfType<ListItem>()
                                       where item.Selected
                                       select Convert.ToInt32(item.Value));

//\\ --- linq query
var messages = from m in myEntities.Messages
select new {
m.Id,
m.MessageText,
m.CreatedByUserID
};

my problem is: i need to get data filtered by selected items from CheckBoxList "selSender" I tried the following:

 RadGrid1.DataSource = messages.Where(m => selSender.Contains(m.CreatedByUserID));

But it's not working, error message:

Instance argument: cannot convert from 'System.Collections.Generic.IEnumerable' to 'System.Linq.IQueryable

How can i get data contains based on selSender id's?

Answer 1

Looks like property CreatedByUserID has type of Nullable<int> . You need to use it's value for verifying if selSender contains it:

RadGrid1.DataSource = from m in myEntities.Messages                          
                      where m.CreatedByUserID.HasValue &&
                            selSender.Contains(m.CreatedByUserID.Value)
                      select new { 
                          m.Id,
                          m.MessageText,
                          m.CreatedByUserID 
                      };