با فرض اینکه دوتا دیتاگرید روی فرمت داشته باشی، یکی برای جدول master و یکی هم details، از این کد استفاده کن :
// this sample code create relation between Customers & Orders tables
SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=northwind;User Id=sa;Password=09126511085;");
SqlCommand cmd = new SqlCommand("select * from customers", con);
SqlDataAdapter adapter = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
// fill dataset with master table (customers)
adapter.Fill(ds, "customers");
// fill datast with child table (orders)
cmd.CommandText = "select * from orders";
adapter.Fill(ds, "orders");
// define this 2 DataColumn for join Customers & Orders tables together
DataColumn dcPK = ds.Tables["customers"].Columns["customerID"];
DataColumn dcFK = ds.Tables["orders"].Columns["customerID"];
// create relation between 2 tables with DataRelation object
DataRelation CustomersToOrders = new DataRelation("CustomersToOrders", dcPK, dcFK);
ds.Relations.Add(CustomersToOrders);
// bind dataGridView1.DataSource to master table
this.dataGridView1.DataSource = ds;
this.dataGridView1.DataMember = "Customers";
// bind dataGridView1.DataSource to our DataRelation(it is child of master table(Customers))
this.dataGridView2.DataSource = ds;
this.dataGridView2.DataMember = "Customers.CustomersToOrders";