Tài liệu Creating and Using a DataViewManager Object pdf

Creating and Using a DataViewManager Object

To create a DataViewManager, you use one of the following constructors:

DataViewManager()

DataViewManager(DataSet myDataSet)

where myDataSet specifies the DataSet used by the DataViewManager object. This sets

the DataSet property of the new DataViewManager object to myDataSet.

Let's take a look at an example of creating and using a DataViewManager. Assume you

have a DataSet named myDataSet, which contains a DataTable populated with rows from

the Customers table. The following example creates a DataViewManager object named

myDVM, passing myDataSet to the constructor:

DataViewManager myDVM = new DataViewManager(myDataSet);

The next example sets the Sort and RowFilter properties that will be used later when a

DataView for the Customers DataTable is created:

myDVM.DataViewSettings["Customers"].Sort = "CustomerID";

myDVM.DataViewSettings["Customers"].RowFilter = "Country = 'UK'";

Note The previous code doesn't actually create a DataView; it merely sets the properties

of any DataView created in the future that views rows from the Customers

DataTable.

The following example actually creates a DataView by calling the CreateDataView()

method of the myDVM DataViewManager, passing the customersDT DataTable to

CreateDataView():

DataView customersDV = myDVM.CreateDataView(customersDT);

The Sort and RowFilter properties of the customersDV DataView are set to CustomerID

and Country = 'UK' respectively. These are the same settings as those set earlier in the

DataViewSettings property.

Listing 13.4A shows a complete example that creates and uses the DataViewManager

shown in this section.

Listing 13.4A: USINGDATAVIEWMANAGER.CS

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