如何使用Entity Framework将数据从多个表绑定到datagridview并使用CRUD操作？

Question

Can some one please give a example of how to bind result to a datagridview which taken from multiple tables (from a join query) in entity framework. actually i can bind data to the datagridview but when i call

context.SaveChanges(); nothing has updated in the database. How to correctly bind data to datagridview with Update,Insert,Delete functions.

This is what i tried.

public class DataBindingProjection
{
    public string dono { get; set; }
    public int apmntid { get; set; }
    public string servicedesc { get; set; }
    public string cusid { get; set; }
    public string empid { get; set; 
    public bool isdelivered { get; set; }
}


context = new HHCSEntities();

var query = from d in context.DeliveryOrders
            join a in context.Appointments on d.ApmntId equals a.ApmntId
            join s in context.ServiceCategories on d.ServiceId equals s.ServiceId
            join e in context.Employees on d.EmpId equals e.EmpId
            select new DataBindingProjection
            {
                dono = d.DONo,
                apmntid = a.ApmntId,
                servicedesc = s.ServiceDesc,
                cusid = a.CusId,
                empid = d.EmpId,
                shortname = e.ShrtName,
                isdelivered = d.IsDelivered
            };

dataGridView1.DataSource = query.ToList();
dataGridView1.Columns[1].DataPropertyName = "dono";
dataGridView1.Columns[2].DataPropertyName = "apmntid";
dataGridView1.Columns[3].DataPropertyName = "servicedesc";
dataGridView1.Columns[4].DataPropertyName = "apmntid";
dataGridView1.Columns[5].DataPropertyName = "empid";
dataGridView1.Columns[9].DataPropertyName = "isdelivered";

Thanks in advance.

Answer 1

After to give result of your query, you should write this:

...

BindingSource bi = new BindingSource();
bi.DataSource = query.ToList();
dataGridView1.DataSource = bi;
dataGridView1.Refresh();

...