gridview colum not sorting

Question

HI ,

i have one datatable  dt  in that i have added few Column

after adding Column in dt. i have given these dt as datasource to gridview

 

once data get loaded in what ever Column i have is not sorting (only date column)

Name Columns is sorting properly  plz help me

 

Dim da As New SqlDataAdapter(Filter, cnn)

dt = New DataTable

da.Fill(dt)

dt.Columns.Add("Col1")

dt.Columns.Add("Col2") 

 

For Each R As DataRow In dt.Rows

ArList = GetLatestLevel(R("ClientID"))

If ArList.Count > 0 Then

R("Col1") = ArList(0).ToString()

R("Col2") = ArList(1).ToString()

End If

Next

 

  dgCall.DataSource = dt

 

 

 

 plz help me