If the DataSet contains multiple tables, an alternative is to create a DataViewManager object, which works something like a global DataSet DataView. This new object provides a single object that manages a collection of DataView objects, each of which is associated with a specific DataTable in the selected DataSet object. You can define individual DataView objects that sort or filter the data in each DataTable; as a matter of fact, ADO.NET creates one for you as it creates each DataT able - all of which can be managed by the DataViewManager.
You can use a DataViewManager to manage view settings for all the tables in a DataSet. If you have a control that you want to bind to multiple tables, such as a grid that navigates relationships, a DataViewManager is ideal.
The DataViewManager contains a collection of DataViewSetting objects that are used to set the view setting of the tables in the DataSet. The DataViewSettingCollection contains one DataViewSetting object for each table in a DataSet . You can set the default ApplyDefaultSort, Sort, RowFilter , and RowStateFilter properties of the referenced table using its DataViewSetting. You can reference the DataViewSetting for a particular table by name or ordinal reference, or by passing a reference to that specific table object. You can access the collection of DataViewSetting objects in a DataViewManager using the DataViewSettings property.
Example
The following code example fills a DataSet with the Northwind database Customers, Orders, and Order Details tables, creates the relationships between the tables, uses a DataViewManager to set default DataView settings, and binds a DataGrid to the DataViewManager. The example sets the default DataView settings for all tables in the DataSet to sort by the primary key of the table (ApplyDefaultSort = true), and then modifies the sort order of the Customers table to sort by CompanyName .
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Data.SqlClient;
namespace WithDataViewManager
{
public class MyDataViewManager : System.Windows.Forms.Form
{
private System.Windows.Forms.DataGrid dataGrid;
private System.ComponentModel.Container components = null;
public MyDataViewManager()
{
InitializeComponent();
// Create a Connection, DataAdapters, and a DataSet.
SqlConnection nwindConn = new SqlConnection(
"server=xeon;database=northwind;uid=sa;pwd=manager");
SqlDataAdapter custDA = new SqlDataAdapter(
"SELECT * FROM Customers", nwindConn);
SqlDataAdapter orderDA = new SqlDataAdapter(
"SELECT * FROM Orders", nwindConn);
SqlDataAdapter ordDetDA = new SqlDataAdapter(
"SELECT * FROM [Order Details]", nwindConn);
DataSet custDS = new DataSet();
// Fill the DataSet with schema information and data.
custDA.MissingSchemaAction = MissingSchemaAction.AddWithKey;
orderDA.MissingSchemaAction = MissingSchemaAction.AddWithKey;
ordDetDA.MissingSchemaAction = MissingSchemaAction.AddWithKey;
custDA.Fill(custDS, "Customers");
orderDA.Fill(custDS, "Orders");
ordDetDA.Fill(custDS, "OrderDetails");
// Create Relationships.
custDS.Relations.Add("CustomerOrders",
custDS.Tables["Customers"].Columns["CustomerID"],
custDS.Tables["Orders"].Columns["CustomerID"]);
custDS.Relations.Add("OrderDetails",
custDS.Tables["Orders"].Columns["OrderID"],
custDS.Tables["OrderDetails"].Columns["OrderID"]);
// Create DataView settings for each Table
// using the DataViewManager
DataViewManager myDVM = new DataViewManager(custDS);
// Loop through the DataViewSettings and set Sort
// or Rowfilter for each Table individually
String myTable;
foreach (DataViewSetting myDVS in myDVM.DataViewSettings)
{
// Set Default Sort Order = Primary Key for all Tables
myDVS.ApplyDefaultSort = true;
// Set individual Sort and Rowfilter ...
myTable = myDVS.Table.ToString();
if (myTable == "Customers")
{
myDVS.Sort = "CompanyName DESC";
}
if (myTable == "Orders")
{
myDVS.RowFilter = "OrderDate >= '01.03.1998'
AND OrderDate <= '31.03.1998'";
}
if (myTable == "OrderDetails")
{
myDVS.RowFilter = "ProductID = 35";
}
}
// ... or directly (the same as above)
myDVM.DataViewSettings["Customers"].Sort =
"CompanyName DESC";
myDVM.DataViewSettings["Orders"].RowFilter =
"OrderDate >= '01.03.1998' AND OrderDate <= '31.03.1998'";
myDVM.DataViewSettings["OrderDetails"].RowFilter =
"ProductID = 35";
// Bind the DataViewManager to a DataGrid
dataGrid.SetDataBinding(myDVM, "Customers");
}
....
....
[STAThread]
static void Main()
{
Application.Run(new MyDataViewManager());
}
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