WinForms Data Grid - Select data rows using mouse without CTRL

C#
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using DevExpress.XtraGrid.Views.Grid;
using DevExpress.XtraGrid.Views.Grid.ViewInfo;
using DevExpress.Utils;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
                private DataTable CreateTable(int RowCount)
                {
            DataTable tbl = new DataTable();
            tbl.Columns.Add("Name", typeof(string));
            tbl.Columns.Add("ID", typeof(int));
            tbl.Columns.Add("Number", typeof(int));
            tbl.Columns.Add("Date", typeof(DateTime));
            for (int i = 0; i < RowCount; i++)
            {
                tbl.Rows.Add(new object[] {string.Format("Name{0}", i), i, 3 - i, DateTime.Now.AddDays(i)});
            }
            return tbl;
                }


        public Form1()
        {
            InitializeComponent();
            gridControl1.DataSource = CreateTable(20);
            MultiSelectionHelper TempMultiSelectionHelper = new MultiSelectionHelper(gridView1);
        }
    }
}

Visual Basic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Windows.Forms

Namespace WindowsApplication1

    Public Partial Class Form1
        Inherits Form

        Private Function CreateTable(ByVal RowCount As Integer) As DataTable
            Dim tbl As DataTable = New DataTable()
            tbl.Columns.Add("Name", GetType(String))
            tbl.Columns.Add("ID", GetType(Integer))
            tbl.Columns.Add("Number", GetType(Integer))
            tbl.Columns.Add("Date", GetType(Date))
            For i As Integer = 0 To RowCount - 1
                tbl.Rows.Add(New Object() {String.Format("Name{0}", i), i, 3 - i, Date.Now.AddDays(i)})
            Next

            Return tbl
        End Function

        Public Sub New()
            InitializeComponent()
            gridControl1.DataSource = CreateTable(20)
            Dim TempMultiSelectionHelper As MultiSelectionHelper = New MultiSelectionHelper(gridView1)
        End Sub
    End Class
End Namespace

C#
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using DevExpress.XtraGrid.Views.Grid;
using DevExpress.XtraGrid.Views.Grid.ViewInfo;
using DevExpress.Utils;

namespace WindowsApplication1
{
    public class MultiSelectionHelper
    {

        private GridView _GridView;
        public MultiSelectionHelper(GridView gridView)
        {
            _GridView = gridView;
            InitProperties();
            SubscribeEvents();
        }
        private void InitProperties()
        {
            _GridView.OptionsBehavior.Editable = false;
            _GridView.OptionsSelection.MultiSelect = true;
            _GridView.OptionsSelection.EnableAppearanceFocusedCell = false;
            _GridView.FocusRectStyle = DrawFocusRectStyle.None;
        }
        private void SubscribeEvents()
        {
            _GridView.MouseDown += _GridView_MouseDown;
        }

        private void _GridView_MouseDown(object sender, MouseEventArgs e)
        {
            OnMouseDown(e);
        }
        private void OnMouseDown(MouseEventArgs e)
        {
            GridHitInfo hi = _GridView.CalcHitInfo(e.Location);
            if (!hi.InRow)
            {
                return;
            }
            _GridView.FocusedRowHandle = hi.RowHandle;
            _GridView.FocusedColumn = hi.Column;
            _GridView.InvertRowSelection(hi.RowHandle);
            DXMouseEventArgs.GetMouseArgs(e).Handled = true;

        }

    }
}

Visual Basic
Imports System.ComponentModel
Imports System.Drawing
Imports System.Windows.Forms
Imports DevExpress.XtraGrid.Views.Grid
Imports DevExpress.XtraGrid.Views.Grid.ViewInfo
Imports DevExpress.Utils

Namespace WindowsApplication1

    Public Class MultiSelectionHelper

        Private _GridView As GridView

        Public Sub New(ByVal gridView As GridView)
            _GridView = gridView
            InitProperties()
            SubscribeEvents()
        End Sub

        Private Sub InitProperties()
            _GridView.OptionsBehavior.Editable = False
            _GridView.OptionsSelection.MultiSelect = True
            _GridView.OptionsSelection.EnableAppearanceFocusedCell = False
            _GridView.FocusRectStyle = DrawFocusRectStyle.None
        End Sub

        Private Sub SubscribeEvents()
            AddHandler _GridView.MouseDown, AddressOf _GridView_MouseDown
        End Sub

        Private Sub _GridView_MouseDown(ByVal sender As Object, ByVal e As MouseEventArgs)
            OnMouseDown(e)
        End Sub

        Private Sub OnMouseDown(ByVal e As MouseEventArgs)
            Dim hi As GridHitInfo = _GridView.CalcHitInfo(e.Location)
            If Not hi.InRow Then
                Return
            End If

            _GridView.FocusedRowHandle = hi.RowHandle
            _GridView.FocusedColumn = hi.Column
            _GridView.InvertRowSelection(hi.RowHandle)
            DXMouseEventArgs.GetMouseArgs(e).Handled = True
        End Sub
    End Class
End Namespace