How to: Respond to Checking Items in CheckedListBoxControl

• Oct 25, 2019
• 4 minutes to read

The following example displays a message box after an item’s check state changes. The example prevents users from toggling the check state of the item with the specified name/description (“Item 0”).

Bound Mode

C#

using DevExpress.XtraEditors;
using DevExpress.XtraEditors.Controls;
using System.ComponentModel;

namespace DXApplication {
    public partial class Form1 : XtraForm {
        BindingList<DataItem> items;
        public Form1() {
            InitializeComponent();
            items = new BindingList<DataItem>() {
                new DataItem(){ Name = "Item 0", Value = 0 },
                new DataItem(){ Name = "Item 1", Value = 1, Checked = true },
                new DataItem(){ Name = "Item 2", Value = 2 }
            };
            checkedListBoxControl1.DataSource = items;
            checkedListBoxControl1.DisplayMember = "Name";
            checkedListBoxControl1.ValueMember = "Value";
            checkedListBoxControl1.CheckMember = "Checked";
            checkedListBoxControl1.ItemChecking += CheckedListBoxControl1_ItemChecking;
            checkedListBoxControl1.ItemCheck += CheckedListBoxControl1_ItemCheck;
        }
        void CheckedListBoxControl1_ItemChecking(object sender, ItemCheckingEventArgs e) {
            CheckedListBoxControl list = (CheckedListBoxControl)sender;
            DataItem item = (DataItem)list.GetItem(e.Index);
            e.Cancel = item.Name == "Item 0";
        }
        //Display a message box after an item's check state changes.
        void CheckedListBoxControl1_ItemCheck(object sender, DevExpress.XtraEditors.Controls.ItemCheckEventArgs e) {
            CheckedListBoxControl checkedListBox = (CheckedListBoxControl)sender;
            DataItem item = (DataItem)checkedListBox.GetItem(e.Index);
            XtraMessageBox.Show($"The check state of '{item.Name}' was changed. New state: {e.State}", "Information");
        }
    }
    public class DataItem {
        public string Name { get; set; }
        public int Value { get; set; }
        public bool Checked { get; set; }
    }
}

VB.NET

Imports DevExpress.XtraEditors
Imports DevExpress.XtraEditors.Controls
Imports System.ComponentModel

Namespace DXApplication
    Partial Public Class Form1
        Inherits XtraForm

        Private items As BindingList(Of DataItem)
        Public Sub New()
            InitializeComponent()
            items = New BindingList(Of DataItem)() From {
                New DataItem() With {
                    .Name = "Item 0",
                    .Value = 0
                },
                New DataItem() With {
                    .Name = "Item 1",
                    .Value = 1,
                    .Checked = True
                },
                New DataItem() With {
                    .Name = "Item 2",
                    .Value = 2
                }
            }
            checkedListBoxControl1.DataSource = items
            checkedListBoxControl1.DisplayMember = "Name"
            checkedListBoxControl1.ValueMember = "Value"
            checkedListBoxControl1.CheckMember = "Checked"
            AddHandler checkedListBoxControl1.ItemChecking, AddressOf CheckedListBoxControl1_ItemChecking
            AddHandler checkedListBoxControl1.ItemCheck, AddressOf CheckedListBoxControl1_ItemCheck
        End Sub
        Private Sub CheckedListBoxControl1_ItemChecking(ByVal sender As Object, ByVal e As ItemCheckingEventArgs)
            Dim list As CheckedListBoxControl = DirectCast(sender, CheckedListBoxControl)
            Dim item As DataItem = CType(list.GetItem(e.Index), DataItem)
            e.Cancel = item.Name = "Item 0"
        End Sub
        'Display a message box after an item's check state changes.
        Private Sub CheckedListBoxControl1_ItemCheck(ByVal sender As Object, ByVal e As DevExpress.XtraEditors.Controls.ItemCheckEventArgs)
            Dim checkedListBox As CheckedListBoxControl = DirectCast(sender, CheckedListBoxControl)
            Dim item As DataItem = CType(checkedListBox.GetItem(e.Index), DataItem)
            XtraMessageBox.Show($"The check state of '{item.Name}' was changed. New state: {e.State}", "Information")
        End Sub
    End Class
    Public Class DataItem
        Public Property Name() As String
        Public Property Value() As Integer
        Public Property Checked() As Boolean
    End Class
End Namespace

Unbound Mode

C#

using DevExpress.XtraEditors;
using DevExpress.XtraEditors.Controls;
using System.Windows.Forms;

namespace DXApplication {
    public partial class Form1 : XtraForm {
        public Form1() {
            InitializeComponent();
            checkedListBoxControl1.Items.AddRange(new CheckedListBoxItem[]{
                new CheckedListBoxItem(0, "Item 0"),
                new CheckedListBoxItem(1, "Item 1", CheckState.Checked),
                new CheckedListBoxItem(2, "Item 2"),
            });
            checkedListBoxControl1.ItemChecking += CheckedListBoxControl1_ItemChecking;
            checkedListBoxControl1.ItemCheck += CheckedListBoxControl1_ItemCheck;
        }
        void CheckedListBoxControl1_ItemChecking(object sender, ItemCheckingEventArgs e) {
            CheckedListBoxControl list = (CheckedListBoxControl)sender;
            CheckedListBoxItem item = (CheckedListBoxItem)list.GetItem(e.Index);
            e.Cancel = item.Description == "Item 0";
        }
        //Display a message box after an item's check state changes.
        void CheckedListBoxControl1_ItemCheck(object sender, DevExpress.XtraEditors.Controls.ItemCheckEventArgs e) {
            CheckedListBoxControl checkedListBox = (CheckedListBoxControl)sender;
            CheckedListBoxItem item = (CheckedListBoxItem)checkedListBox.GetItem(e.Index);
            XtraMessageBox.Show($"The check state of '{item.Description}' was changed. New state: {e.State}", "Information");
        }
    }
}

VB.NET

Imports DevExpress.XtraEditors
Imports DevExpress.XtraEditors.Controls
Imports System.Windows.Forms

Namespace DXApplication
    Partial Public Class Form1
        Inherits XtraForm

        Public Sub New()
            InitializeComponent()
            checkedListBoxControl1.Items.AddRange(New CheckedListBoxItem(){
                New CheckedListBoxItem(0, "Item 0"),
                New CheckedListBoxItem(1, "Item 1", CheckState.Checked),
                New CheckedListBoxItem(2, "Item 2")
            })
            AddHandler checkedListBoxControl1.ItemChecking, AddressOf CheckedListBoxControl1_ItemChecking
            AddHandler checkedListBoxControl1.ItemCheck, AddressOf CheckedListBoxControl1_ItemCheck
        End Sub
        Private Sub CheckedListBoxControl1_ItemChecking(ByVal sender As Object, ByVal e As ItemCheckingEventArgs)
            Dim list As CheckedListBoxControl = DirectCast(sender, CheckedListBoxControl)
            Dim item As CheckedListBoxItem = CType(list.GetItem(e.Index), CheckedListBoxItem)
            e.Cancel = item.Description = "Item 0"
        End Sub
        'Display a message box after an item's check state changes.
        Private Sub CheckedListBoxControl1_ItemCheck(ByVal sender As Object, ByVal e As DevExpress.XtraEditors.Controls.ItemCheckEventArgs)
            Dim checkedListBox As CheckedListBoxControl = DirectCast(sender, CheckedListBoxControl)
            Dim item As CheckedListBoxItem = CType(checkedListBox.GetItem(e.Index), CheckedListBoxItem)
            XtraMessageBox.Show($"The check state of '{item.Description}' was changed. New state: {e.State}", "Information")
        End Sub
    End Class
End Namespace