private void Hostel_select_Load(object sender, EventArgs e)
{
ORMDataContext a1 = new ORMDataContext();
Hostel_find h1 = new Hostel_find();
var query = from Hostel_find in a1.Hostel_finds
where Hostel_find.A_name == sel
select Hostel_find.H_name;
comboBox1.ValueMember = "H_name";
comboBox1.DisplayMember = "H_name";
comboBox1.DataSource = query;
var query1 = from Cost_info in a1.Cost_infos
where Cost_info.name == comboBox1.SelectedItem.ToString()
select Cost_info;
dataGridView1.DataSource = query1;
}
partial void DeleteHostel_find(Hostel_find instance);
partial void UpdateHostel_find(Hostel_find instance);
partial void InsertHostel_find(Hostel_find instance);