Cell Selection

Jan 08, 2024
4 minutes to read

The GridControl allows you to select cells and their ranges.

Enable Multiple Cell Selection

To enable multiple cell selection:

Check that the DataViewBase.NavigationStyle property is set to GridViewNavigationStyle.Cell (default value).
Set the DataControlBase.SelectionMode property to MultiSelectMode.Cell.

In this mode, the GridControl considers the row with the focused cell as a focused row.

Property	Description
DataControlBase.CurrentItem	Returns the latest selected object (focused row).
DataControlBase.SelectedItem	Returns the first selected object (the first item in the DataControlBase.SelectedItems collection).
DataControlBase.SelectedItems	Contains the row’s data items that contain the selected cells.

Refer to the Select Multiple Cells topic for information on how end users can select cells in the multiple cell selection mode.

Selection Availability

Handle the TableView.CanSelectCell / TreeListView.CanSelectCell or TableView.CanUnselectCell / TreeListView.CanUnselectCell event to control whether users can select or unselect cells:

XAML

xaml

<dxg:GridControl x:Name="grid"
                 SelectionMode="Cell">
    <dxg:GridControl.View>
        <dxg:TableView x:Name="view"
                       CanSelectCell="View_CanSelectCell"
                       CanUnselectCell="View_CanUnselectCell">
        </dxg:TableView>
    </dxg:GridControl.View>
</dxg:GridControl>

C#
VB.NET

csharp

void View_CanSelectCell(object sender, CanSelectCellEventArgs e) {
    e.CanSelectCell = e.Column.FieldName != "Visits";
}
void View_CanUnselectCell(object sender, CanUnselectCellEventArgs e) {
    e.CanUnselectCell = e.Column.FieldName != "Birthday";
}

Class SurroundingClass
    Private Sub View_CanSelectCell(ByVal sender As Object, ByVal e As CanSelectCellEventArgs)
        e.CanSelectCell = e.Column.FieldName <> "Visits"
    End Sub

    Private Sub View_CanUnselectCell(ByVal sender As Object, ByVal e As CanUnselectCellEventArgs)
        e.CanUnselectCell = e.Column.FieldName <> "Birthday"
    End Sub
End Class

Select Cells

API	Description
DataControlBase.BeginSelection	Prevents selection updates until the DataControlBase.EndSelection method is called.
DataControlBase.EndSelection	Enables selection updates previously suppressed by a DataControlBase.BeginSelection method call. Forces a selection update.
TableView.SelectCell / TreeListView.SelectCell	Selects the cell identified by its row handle and column.
TableView.SelectCells / TreeListView.SelectCells	Selects multiple cells.
TableView.UnselectCell / TreeListView.UnselectCell	Unselects the specified cell.
TableView.UnselectCells / TreeListView.UnselectCells	Unselects multiple cells.
TableView.GetSelectedCells / TreeListView.GetSelectedCells	Returns a collection of selected cells in the TableView / TreeListView.
GridControl.GetSelectedRowHandles	Returns the handles of the rows that contain the selected cells.
DataControlBase.SelectedItemChanged	This event occurs after the GridControl‘s primary selected item is changed.
GridControl.SelectionChanged / TreeListControlBase.SelectionChanged	This event occurs after the GridControl‘s / TreeListControl‘s selection is changed.

The following code sample demonstrates how to iterate through cells and select cells that contain the specified value:

C#
VB.NET

csharp

void Button_Click(object sender, RoutedEventArgs e) {
    SelectCellInColumn(8);
}
public void SelectCellInColumn(object value) {
    grid.BeginSelection();
    grid.UnselectAll();
    for (int index = 0; index < grid.VisibleRowCount; index++) {
        var rowHandle = grid.GetRowHandleByVisibleIndex(index);
        var cellValue = grid.GetCellValue(rowHandle, "Visits");
        if (cellValue != null && cellValue.Equals(value))
            view.SelectCell(rowHandle, grid.Columns["Visits"]);
    }
    grid.EndSelection();
}

Private Sub Button_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    SelectCellInColumn(8)
End Sub

Public Sub SelectCellInColumn(ByVal value As Object)
    grid.BeginSelection()
    grid.UnselectAll()
    For index As Integer = 0 To grid.VisibleRowCount - 1
        Dim rowHandle = grid.GetRowHandleByVisibleIndex(index)
        Dim cellValue = grid.GetCellValue(rowHandle, "Visits")
        If cellValue IsNot Nothing AndAlso cellValue.Equals(value) Then view.SelectCell(rowHandle, grid.Columns("Visits"))
    Next
    grid.EndSelection()
End Sub

Obtain Selected Cells

Use the TableView.GetSelectedCells / TreeListView.GetSelectedCells method to obtain selected cells. This method returns an array of GridCell objects that contain cell coordinates (row and column).

This code sample demonstrates how to obtain display text from selected cells:

C#
VB.NET

csharp

public IEnumerable<string> GetCellsDisplayText() {
    var list = new List<string>();
    foreach (var cell in view.GetSelectedCells())
        list.Add(grid.GetCellDisplayText(cell.RowHandle, cell.Column));
    return list;
}

Public Function GetCellsDisplayText() As IEnumerable(Of String)
    Dim list = New List(Of String)()

    For Each cell In view.GetSelectedCells()
        list.Add(grid.GetCellDisplayText(cell.RowHandle, cell.Column))
    Next

    Return list
End Function

Change Selected Cell Appearance

You can change a cell’s appearance according to its selection state. To set a cell’s appearance for the entire GridControl, use the DataViewBase.CellStyle property; for individual columns, use ColumnBase.CellStyle.

Use the LightweightCellEditor.SelectionState property to determine the cell state:

Name	Description
None	A cell is not focused and is not selected.
Focused	A cell is focused but is not selected.
Selected	A cell is selected but is not focused.
FocusedAndSelected	A cell is focused and selected.
Highlighted	A cell is highlighted.
CellMerge	A cell is not focused and is not selected, and the TableView.AllowCellMerge property is set to true.

The following code sample changes the background color of cells based on their states:

View Example: Change the Appearance of Focused and Selected Cells

XAML

xaml

<dxg:GridColumn FieldName="Visits" IsSmart="True">
    <dxg:GridColumn.CellStyle>
        <Style TargetType="dxg:LightweightCellEditor">
            <Style.Triggers>
                <Trigger Property="SelectionState" Value="Selected">
                    <Setter Property="Background" Value="LightGreen"/>
                </Trigger>
                <Trigger Property="SelectionState" Value="FocusedAndSelected">
                    <Setter Property="Background" Value="Green"/>
                </Trigger>
            </Style.Triggers>
        </Style>
    </dxg:GridColumn.CellStyle>
</dxg:GridColumn>