Get Data based on FromDate and ToDate using Linq in ASP.Net

I am done with this

i select data from table1 and fill in drop-down 

data is

RID    Rname   startdate     enddate
 
1       Kh     2014-02-1    2014-02-28

2      Il      2014-04-02   2014-04-07

3      UH     2015-01-04    2015-04-20

AND so on

i concatenate query and fill  drop-down  so data in drop-down  is like this

Kh          2014-02-1  2014-02-28

Il         2014-04-02   2014-04-07

UH         2015-01-04    2015-04-20

and then when i select data from drop-down  then against this another data from another table (e.g. table2 ) is display in grid-view i.e.

i select KH so Kh RID is 1 

so in according  RID data is.. i display that data in grid-view and i am done with this

ID	OName	         RegNo	     RID
1	han	          29          1	
2	Sah	          91	      1 
3	Max 	          995	      1
4	Rbal	          97	      1

but now the process is changes

i fill dropdown only with  Rname and i place two calendars

e,g.

<input type="date" ID="from_date"/>  
<input type="date" ID="to_date"/> 

now i want when i select value from dropdown and select date from calendar then i want to display data on behalf of this

query which i try

T1 ts = new T1();
            var list1 = ts.table2.ToList();
            var dq = (from reg_data in list1
                      where reg_data.RID == Convert.ToInt32(regiondrop.SelectedValue)
                      orderby reg_data.OName
                      select new
                      {
                          ID = reg_data.ID,
                          OName = reg_data.OName,
                          RegNo = reg_data.RegNo,
                         RID = reg_data.RID,
                         

                      }).ToList();
            GridView1.DataSource = dq;
            GridView1.DataBind();

any solution?