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Getting Typed DataRows from DataViews

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[ Team LiB ] Recipe 3.11 Getting Typed DataRows from DataViews Problem When using a DataView to find rows in a typed DataSet, you want to convert the rows you find to typed DataRow objects having all the properties and methods defined in your typed DataSet. | Team LiB Recipe 3.11 Getting Typed DataRows from DataViews Problem When using a DataView to find rows in a typed DataSet you want to convert the rows you find to typed DataRow objects having all the properties and methods defined in your typed DataSet. Solution Cast the DataRow object returned by the Row property of a DataRowView to a typed DataRow. The sample code contains two event handlers Form.Load Sets up the sample by creating a typed DataSet containing the Categories table from the Northwind sample database. The default view of the typed Categories table sorted by the CategorylD is bound to the data grid on the form. Find Button.Click Finds the row in the view matching the user specified CategorylD gets the underlying table row and casts that to the typed row. The C code is shown in Example 3-11. Example 3-11. File TypedDataRowFromDataViewForm.es Namespaces variables and constants using System using System.Configuration using System.Windows.Forms using System.Text using System.Data using System.Data.SqlClient private DataView dv Table name constants private const String CATEGORIES_TABLE Categories . . . private void TypedDataRowFromDataViewForm_Load object sender System.EventArgs e Create the typed DataSet. CategoriesDS dsTyped new CategoriesDS Create and fill the Categories table. String sqlText SELECT CategorylD CategoryName Description FROM Categories SqlDataAdapter da new SqlDataAdapter sqlText ConfigurationSettings.AppSettings S ql_ConnectString da.Fill dsTyped.Categories Get the default view and set the sort key. dv dsTyped.Categories.DefaultView dv.Sort CategorylD Bind the default view of the Categories table to the grid. dataGrid.DataSource dv private void findButton_Click object sender System.EventArgs e int categoryld 0 try categoryld Convert.ToInt32 categoryIdTextBox.Text Get the index of the find row in the view. int viewRowIndex dv.Find categoryld if viewRowIndex -1 MessageBox.Show Row not found for Category ID categoryId else Cast the .