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BeforeSelectChange Event

Occurs before one or more row, cell, or column objects are selected or deselected.
Syntax
'Declaration
 
Public Event BeforeSelectChange As BeforeSelectChangeEventHandler
public event BeforeSelectChangeEventHandler BeforeSelectChange
Event Data

The event handler receives an argument of type BeforeSelectChangeEventArgs containing data related to this event. The following BeforeSelectChangeEventArgs properties provide information specific to this event.

PropertyDescription
Cancel (Inherited from System.ComponentModel.CancelEventArgs) 
NewSelections new selections (read-only)
Type select change value (read-only)
Remarks

The selectchange argument indicates what type of object or objects were involved in the selection: rows, cells, or columns. When a row or column is selected, the cells contained in it are not considered selected.

The newselections argument returns a reference to a Selected collection that can be used to retrieve references to the rows, cells, or columns that will be selected. You can use this reference to access any of the returned collection's properties or methods, as well as the properties or methods of the objects within the collection.

The cancel argument enables you to programmatically prevent the object or objects from being selected. This argument can be used to prevent the user from changing the selection unless a certain condition is met.

This event is generated before one or more objects have been selected or deselected, either programmatically, or by user interaction.

The control's Selected property can be used to determine what object or objects were previously selected.

The AfterSelectChange event, which occurs after one or more row, cell, or column objects have been selected or deselected, is generated after this event.

Note: This event will fire when one or more rows are deleted through the grid, but this cannot be cancelled. If the action needs to be cancelled, the BeforeRowsDeleted event should be used instead.

Example
Following code shows some of the information available in BeforeSelectChange event and its potential uses.

For an overview of how to handle events in Visual Basic or Visual C#, see Event Handlers in Visual Basic and Visual C#. For specific information and code examples illustrating how to consume events in your application, see Consuming Events in the .NET Framework Developer's Guide.

Imports Infragistics.Shared
Imports Infragistics.Win
Imports Infragistics.Win.UltraWinGrid
Imports System.Diagnostics

   Private Sub UltraGrid1_BeforeSelectChange(ByVal sender As Object, ByVal e As Infragistics.Win.UltraWinGrid.BeforeSelectChangeEventArgs) Handles ultraGrid1.BeforeSelectChange

       ' BeforeSelectChange gets fired when the user selects rows, columns or cells.
       ' NewSelections property off the passed in event args has the new selection.
       ' Type specifies whether the change in selection was with rows, columns or
       ' cells. This also gives you a chance to cancel the new selection by setting
       ' the Cancel property off the event args. If cancelled, the UltraGrid will go
       ' back to previous selection.

       Debug.Write("BeforeSelectChange: ")

       ' Check the type to find out whether rows, columns or cells were selected.
       If e.Type Is GetType(UltraGridGroupByRow) Then

           ' Item type is a group-by-row so use Rows property off the Selected to access those items.
           If e.NewSelections.Rows.Count = 0 Then
               Debug.WriteLine("Group-by rows are being unselected.")
           Else
               Debug.WriteLine(e.NewSelections.Rows.Count & " group-by rows are being selected.")
           End If

       ElseIf e.Type Is GetType(UltraGridRow) Then

           ' Item type is a row so use Rows property off the Selected to access those items.
           If e.NewSelections.Rows.Count = 0 Then
               Debug.WriteLine("Rows are being unselected.")
           Else
               Debug.WriteLine(e.NewSelections.Rows.Count & " rows are being selected.")
           End If

       ElseIf e.Type Is GetType(UltraGridColumn) Then

           ' Item type is a column so use Columns property off the Selected to access those items.
           If e.NewSelections.Columns.Count = 0 Then
               Debug.WriteLine("Columns are being unselected.")
           Else
               Debug.WriteLine(e.NewSelections.Columns.Count & " columns are being selected.")
           End If

       ElseIf e.Type Is GetType(UltraGridCell) Then

           ' Item type is a cell so use Cells property off the Selected to access those items.
           If e.NewSelections.Cells.Count = 0 Then
               Debug.WriteLine("Columns are being unselected.")
           Else
               Debug.WriteLine(e.NewSelections.Cells.Count & " cells are being selected.")
           End If

       End If
   End Sub
using Infragistics.Shared;
using Infragistics.Win;
using Infragistics.Win.UltraWinGrid;
using System.Diagnostics;

private void ultraGrid1_BeforeSelectChange(object sender, Infragistics.Win.UltraWinGrid.BeforeSelectChangeEventArgs e)
{

	// BeforeSelectChange gets fired when the user selects rows, columns or cells.
	// NewSelections property off the passed in event args has the new selection.
	// Type specifies whether the change in selection was with rows, columns or
	// cells. This also gives you a chance to cancel the new selection by setting
	// the Cancel property off the event args. If cancelled, the UltraGrid will go
	// back to previous selection.

	Debug.Write( "BeforeSelectChange: " );

	// Check the type to find out whether rows, columns or cells were selected.
	if ( typeof( UltraGridGroupByRow ) == e.Type )
	{
		// Item type is a group-by-row so use Rows property off the Selected to access those items.
		if ( e.NewSelections.Rows.Count == 0 )
			Debug.WriteLine( "Group-by rows are being unselected." );
		else
			Debug.WriteLine( e.NewSelections.Rows.Count + " group-by rows are being selected." );
	} 
	else if ( typeof( UltraGridRow ) == e.Type )
	{
		// Item type is a row so use Rows property off the Selected to access those items.
		if ( e.NewSelections.Rows.Count == 0 )
			Debug.WriteLine( "Rows are being unselected." );
		else
			Debug.WriteLine( e.NewSelections.Rows.Count + " rows are being selected." );
	}
	else if ( typeof( UltraGridColumn ) == e.Type )
	{
		// Item type is a column so use Columns property off the Selected to access those items.
		if ( e.NewSelections.Columns.Count == 0 )
			Debug.WriteLine( "Columns are being unselected." );
		else
			Debug.WriteLine( e.NewSelections.Columns.Count + " columns are being selected." );
	}
	else if ( typeof( UltraGridCell ) == e.Type )
	{
		// Item type is a cell so use Cells property off the Selected to access those items.
		if ( e.NewSelections.Cells.Count == 0 )
			Debug.WriteLine( "Columns are being unselected." );
		else
			Debug.WriteLine( e.NewSelections.Cells.Count + " cells are being selected." );
	}	
									
}
Requirements

Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Server 2012, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

See Also