I am stil discussing this issue with our developer. I will inform you if there is any update / progress regrading this issue.

Have you planned a update for this issue?

We need this function before buying WebGrid 7, how much time we must wait?

Thanks, Nicola

Sorry for the late reply, you are correct currently WebGrid 7 has not supported this feature yet. However an enchancement is being developed and is scheduled to be ready in the next WebGrid 7 build.

protected void wgTest_InitializeDataSource(object sender, ISNet.WebUI.WebGrid.DataSourceEventArgs e)
{
    NorthwindV2DataContext northwind = new NorthwindV2DataContext();

    var query = from c in northwind.Customers
                select c;

    e.DataSource = query.ToList();

}

protected void wgTest_PreInitialize(object sender, EventArgs e)
{
    NorthwindV2DataContext northwindContenxt = new NorthwindV2DataContext();
    
    // assign OnPreInitialize event in ASPX
    // defines the Object Relations
    ArrayList objectRelations = new ArrayList();
    objectRelations.Add(new WebGridObjectRelation(
            typeof(List<Customer>), "CustomerID", "Orders",
            typeof(List<Order>), "CustomerID"));

    // defines the Parent and Child Type information
    // objectTypes contains 3 object array: The parent collection type,
    // child item type, the primary keys of child collection
    // Primary keys can be string (if only 1 primary key defined),
    // or array of string for multiple primary keys scenario.
    ArrayList objectTypes = new ArrayList();
    objectTypes.Add(new object[] {
        typeof(List<Customer>), typeof(Customer), "CustomerID"});
    objectTypes.Add(new object[] {
        typeof(List<Order>), typeof(Order), "OrderID"});

    // assign the required definitions through SetObjectRelations method
    // the SetObjectRelations need to be called in new PreInitialize method
    // since it needs to be initialized in earliest phase.
    wgTest.SetObjectRelations(objectRelations, objectTypes);

}