private void button1_Click(object sender, EventArgs e)
{
// create data source
var contacts = new IndexedCollection <Contact>();
// bind list to grid (before adding elements)
this.dataGridView1.DataSource =
from c in contacts.AsLive()
where c.Name.Contains("g")
select c;
// add elements to collection (after binding)
foreach (string s in names.Split(','))
{
contacts.Add(new Contact()
{
Name = s
});
}
}
public Form1()
{
InitializeComponent();
using (var xmlStream = Assembly.GetExecutingAssembly().GetManifestResourceStream("LiveViewsObjects.Northwind.xml"))
{
System.Diagnostics.Debug.Assert(xmlStream != null);
XmlReaderSettings settings = new XmlReaderSettings {
IgnoreWhitespace = true
};
XmlReader reader = XmlReader.Create(xmlStream, settings);
// Filling the collections with base data
XDocument doc = XDocument.Load(reader);
foreach (XElement c in doc.Descendants("Customers"))
{
customers.Add(new Customer
{
CustomerID = (string)c.Element("CustomerID"),
City = (string)c.Element("City"),
DateRegistered = (DateTime)c.Element("DateRegistered")
});
}
foreach (XElement o in doc.Descendants("Orders"))
{
orders.Add(new Order
{
OrderID = (int)o.Attribute("OrderID"),
CustomerID = (string)o.Attribute("CustomerID"),
ShipCity = (string)o.Attribute("ShipCity"),
});
}
}
// Creating indexes. It is optional, only for performance optimization.
// If you delete this, the functionality will be the same and slowdown will be noticeable only on large data sets.
customers.Indexes.Add(c => c.CustomerID, true);
orders.Indexes.Add(o => o.CustomerID);
orders.Indexes.Add(o => o.ShipCity);
//...end of creating indexes
// Make the base data collection live:
View <Customer> customersView = customers.AsLive();
View <Order> ordersView = orders.AsLive().AsUpdatable(); // AsUpdatable() makes it possible for
// the user to change data directly in the grid showing the join view below.
// Order fields can be changed by the user there, Customer fields can't be changed by the user
// Specifying this argument is needed only if you need to change data directly in the view instead
// of changing the base data, and then only for query operators with more than one argument such as Join.
// Creating a live view over the base data
IListSource view =
from o in ordersView
where o.ShipCity == "London" || o.ShipCity == "Colchester"
select o;
ShowViewInGrid(view, dataGridView1);
// Creating another live view over the base data
customerOrderView =
from c in customersView
join o in ordersView on c.CustomerID equals o.CustomerID
where o.ShipCity == "London" || o.ShipCity == "Colchester"
// Using a user-defined class like CustomerOrder is not mandatory. Anonymous class could be used instead as in the
// query above, but in that case we could not assign it to a variable like customerOrderView, defined outside
// of the scope of this method, because anonymous classes are only available in local scope.
select new CustomerOrder {
CustomerID = c.CustomerID, City = c.City, OrderID = o.OrderID, ShipCity = o.ShipCity
};
ShowViewInGrid(customerOrderView, dataGridView2);
// See the readme.txt file in the project folder for a description of the live view functionality you can try in this sample
}
