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SelectedIndex = -1; } In some cases you ll want to go even further and make sure a selected row remains selected when sorting changes The trick here is to store the selected value of the key field in view state each time the selected index changes: protected void GridView1_SelectedIndexChanged(object sender, EventArgs e) { // Save the selected value if (GridView1SelectedIndex != -1) { ViewState["SelectedValue"] = GridView1SelectedValueToString(); } } Now, when the grid is bound to the data source (for example after a sort operation), you can reapply to the last selected index: protected void GridView1_DataBound(object sender, EventArgs e) { if (ViewState["SelectedValue"] != null) { string selectedValue = (string)ViewState["SelectedValue"]; // Reselect the last selected row foreach (GridViewRow row in GridView1Rows) { string keyValue = GridView1DataKeys[rowRowIndex]ValueToString(); if (keyValue == selectedValue) { GridView1SelectedIndex = row.

Sometimes you may run into a problem in which the property names of your data class don t exactly match the parameter names of your update method. If all you need is a simple renaming job, you need to perform the task that was described in the Updating with Stored Procedures section earlier, although the syntax is slightly different. First, you define the additional parameters you need, with the correct names. For example, maybe you need to rename the EmployeeDetails.EmployeeID property to a parameter named id in the update method. Here s the new parameter you need: <asp:ObjectDataSource ID="sourceEmployees" runat="server" TypeName="DatabaseComponent.EmployeeDB" SelectMethod="GetEmployees" UpdateMethod="UpdateEmployee" OnUpdating="sourceEmployees_Updating" > <UpdateParameters> <asp:Parameter Name="id" Type="Int32" /> </UpdateParameters> </asp:ObjectDataSource> Second, you react to the ObjectDataSource.Updating event, setting the value for these parameters and removing the ones you don t want: protected void sourceEmployees_Updating(object sender, ObjectDataSourceMethodEventArgs e) { e.InputParameters["id"] = e.InputParameters["EmployeeID"]; e.InputParameters.Remove("EmployeeID"); }

SortExpression) ' matches the requested sort (eSortExpression) ' This code tries to match the beginning of the GridView ' sort expression The final ASC or DESC part is ignored If GridView1SortExpressionStartsWith(eSortExpression) Then ' This sort is being applied to the same field for the second time ' Reverse it If GridView1SortDirection = SortDirectionAscending Then ' This takes care of automatically adding the "DESC" ' to the end of the sort expression eSortDirection = SortDirectionDescending End If End If End Sub You could use similar logic to turn clicks on different columns into a compound sort For example, you might want to check if the user clicks LastName and then FirstName In this case, you could apply a LastName+FirstName sort Protected Sub GridView1_Sorting( ByVal sender As Object, ByVal e As GridViewSortEventArgs) If eSortExpression = "FirstName" AndAlso GridView1.

RowIndex; return; } } } } Keep in mind that this approach can be confusing if you also have enabled paging (which is described later in the section Paging the GridView ) That s because a sorting operation might move the current row to another page, rendering it not visible but keeping it selected This is a perfectly valid situation from a code standpoint but confusing in practice..

The same approach used here for updating applies when you re performing inserts and deletes. The only difference is that you handle the Inserting and Deleting events instead.

SortExpression = "LastName" Then ' Based on the current sort and the requested sort, a compound ' sort makes sense eSortExpression = "LastName, FirstName" End If End Sub.

The GridView s sorting is straightforward it supports sorting by any sortable column in ascending order In some applications, the user has more sorting options or can order lengthy result sets with more complex sorting expressions Your first avenue for improving sorting with the GridView is to handle the GridViewSorting event, which occurs just before the sort is applied At this point, you can change the sorting expression For example, you could use this to implement an ascending/descending sort pattern With this pattern, you click a column once to apply an ascending sort and a second time to apply a descending sort This is similar to the sorting that s built into Windows Explorer Here s the code you need to implement this approach: protected void GridView1_Sorting(object sender, GridViewSortEventArgs e) { // Check to see the if the current sort (GridView1SortExpression) // matches the requested sort (eSortExpression).