ROHIT says:
newListItem.Text = myReader.GetValue(myReader.GetOrdinal("SH_NAME"))
newListItem.Value = myReader.GetValue(myReader.GetOrdinal("SH_NAME"))
Here you have to use id for value field like
newListItem.Value = myReader.GetValue(myReader.GetOrdinal("SH_ID"))
So that you will able to get value like below to apply the condition.
Dim selectedValue As Integer = Convert.ToInt32(ddltype.SelectedValue)