Disable CheckedListBox Items

Question

i'm using vs 2003 and vb.net to development a window application. i have a checkboxlist that contains few items. i need to disable some of the items, meaning the checked  could not be modified after being saved into the database. the purpose of doing this because i want to show user the item they redeemed. please tell me how to do that. thanks for any help.

Answer 1

Hi,engloon

      your question has been asked before,please refer this thread

      http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=173121&SiteID=1

 

     I think a better solution would be to not include these items in the list.

     Hope this helps.

Answer 2

hi Gavin.
i saw that thread before, but i was still trying to make it happen.
i've decided to use 2 different checkedlistboxes to display enabled and disabled items.
thanks for your advise.

Answer 3

In fact, the checkListBox is kind of ListBox, so make a ListBox to work as a CheckListBox, take my example:

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Text;

using System.Windows.Forms;

 

namespace Sample2

{

    public partial class CheckListBoxTest : Form

    {

        public CheckListBoxTest()

        {

            InitializeComponent();

        }

 

        private void CheckListBoxTest_Load(object sender, EventArgs e)

        {

            DataTable dt = new DataTable();

            dt.Columns.Add("name");

            dt.Columns.Add("status",typeof(bool));

            for (int j = 0; j < 20; j++)

            {

                dt.Rows.Add("checkbox"+j.ToString(), j%2);

            }

 

            CheckBox[] cks = new CheckBox[dt.Rows.Count];

            for (int j = 0; j < dt.Rows.Count; j++)

            {

                cks[j] = new CheckBox();

                cks[j].Text = "";

                cks[j].Checked = (bool)dt.Rows[j]["status"];

                cks[j].Enabled = !cks[j].Checked;

                cks[j].Height = this.listBox1.ItemHeight;

                cks[j].Width = 15;

                cks[j].Location = new Point(0, this.listBox1.ItemHeight * j);

                this.listBox1.Controls.Add(cks[j]);

                this.listBox1.Items.Add(dt.Rows[j]["name"].ToString());

            }

            this.listBox1.DrawMode = DrawMode.OwnerDrawFixed;

            this.listBox1.DrawItem += new DrawItemEventHandler(listBox1_DrawItem);

        }

 

        void listBox1_DrawItem(object sender, DrawItemEventArgs e)

        {

            e.DrawBackground();

            Rectangle contentRect = e.Bounds;

            contentRect.X = 16;

            e.Graphics.DrawString(this.listBox1.Items[e.Index].ToString(),

                e.Font,

                new SolidBrush(e.ForeColor),

                contentRect);

        }

    }

}

Answer 4

For those who use VB.NET, I translate my sample above to VB.NET for you:

Public Class CheckListBoxTest

    Inherits Form

 

    Public Sub New()

        MyBase.New()

        InitializeComponent()

    End Sub

 

    Private Sub CheckListBoxTest_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load

        Dim dt As DataTable = New DataTable

        dt.Columns.Add("name")

        dt.Columns.Add("status", GetType(System.Boolean))

        Dim j As Integer = 0

        Do While (j < 20)

            dt.Rows.Add(("checkbox" + j.ToString), (j Mod 2))

            j = (j + 1)

        Loop

 

        j = 0

        Dim n = dt.Rows.Count

        Dim cks(n) As CheckBox

        Do While (j < dt.Rows.Count)

            cks(j) = New CheckBox

            cks(j).Text = ""

            cks(j).Checked = CType(dt.Rows(j)("status"), Boolean)

            cks(j).Enabled = Not cks(j).Checked

            cks(j).Height = Me.ListBox1.ItemHeight

            cks(j).Width = 15

            cks(j).Location = New Point(0, (Me.ListBox1.ItemHeight * j))

            Me.ListBox1.Controls.Add(cks(j))

            Me.ListBox1.Items.Add(dt.Rows(j)("name"))

            j = (j + 1)

        Loop

        Me.ListBox1.DrawMode = DrawMode.OwnerDrawFixed

        AddHandler ListBox1.DrawItem, AddressOf Me.listBox1_DrawItem

    End Sub

 

    Private Sub listBox1_DrawItem(ByVal sender As Object, ByVal e As DrawItemEventArgs)

        e.DrawBackground()

        Dim contentRect As Rectangle = e.Bounds

        contentRect.X = 16

        e.Graphics.DrawString(Me.listBox1.Items(e.Index).ToString, e.Font, New SolidBrush(e.ForeColor), contentRect)

    End Sub

 

End Class

 

Answer 5

In current example you can use specific wrapper - CheckedListBoxItem, which has Enabled property.
Visual Studio 2008
.net framework 2.0
C#

/// <summary>
/// CheckedListBox control with enabling.
/// </summary>
public class CheckedListBoxEx : CheckedListBox
{
/// <summary>
/// CheckedListBoxItem item.
/// </summary>
public class CheckedListBoxItem
{
/// <summary>
/// Constructor
/// </summary>
/// <param name="text"></param>
public CheckedListBoxItem(string text)
: this(text, true)
{ }

/// <summary>
/// Constructor
/// </summary>
/// <param name="text"></param>
/// <param name="enabled"></param>
public CheckedListBoxItem(string text, bool enabled)
{
this.Text = text;
this.Enabled = enabled;
}

/// <summary>
/// Text
/// </summary>
public string Text
{
get;
private set;
}

/// <summary>
/// Enabling
/// </summary>
public bool Enabled
{
get;
private set;
}

/// <summary>
/// To string.
/// </summary>
/// <returns></returns>
public override string ToString()
{
return this.Text;
}
}

/// <summary>
/// On drawn item override.
/// </summary>
/// <param name="e"></param>
protected override void OnDrawItem(DrawItemEventArgs e)
{
CheckedListBoxItem item = null;
if (e.Index >= 0 && e.Index < this.Items.Count)
item = this.Items[e.Index] as CheckedListBoxItem;

DrawItemEventArgs ne = e;

if (item != null && !item.Enabled)
{
ne = new DrawItemEventArgs(
e.Graphics,
e.Font,
e.Bounds,
e.Index,
e.State,
System.Drawing.SystemColors.InactiveCaptionText,
e.BackColor);
}
base.OnDrawItem(ne);
}

/// <summary>
/// On Item Check override.
/// </summary>
/// <param name="ice"></param>
protected override void OnItemCheck(ItemCheckEventArgs ice)
{
CheckedListBoxItem item = this.Items[ice.Index] as CheckedListBoxItem;

if (item != null && !item.Enabled)
ice.NewValue = ice.CurrentValue;

base.OnItemCheck(ice);
}
}

Answer 6

Hi Stepan Chu,

Even i am looking to enable/disable a particular CheckedListBox item in a given CheckedListBox control.

I saw the wrapper class implementation. Please share some working sample based on this wrapper class implemenation.

regards,
Karvee

Answer 7

Stepan,

Don't know if anyone has come up with a better solution, but your CheckedListBoxEx worked nicely for me.  Took all of 3 minutes to incorporate into my project.  Would be nice to show the checkbox itself dimmed, but the behavior of your class fits the bill.  Thanks for sharing this.

-kirk