Populate and Update CheckBoxList value from database using C# in ASP.Net

Hi Chriz,

I have created sample code which fullfill your requirement.

HTML

<div>
    <asp:Panel ID="pnlUser" runat="server">
        <asp:CheckBoxList ID="chkUsers" runat="server">
        </asp:CheckBoxList>
    </asp:Panel>
    <asp:Button ID="btnUpdate" OnClick="OnUpdate" Text="Update" runat="server" />
</div>

C#

private string constring = ConfigurationManager.ConnectionStrings["Constring"].ToString();
DataTable dt = new DataTable();
protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.PopulatesUsersName();
    }
}

private void PopulatesUsersName()
{
    using (SqlConnection con = new SqlConnection(constring))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT  *  FROM Category", con))
        {

            using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
            {
                sda.Fill(dt);
                ViewState["Data"] = dt;
                chkUsers.DataSource = dt;
                chkUsers.DataTextField = "Category";
                chkUsers.DataValueField = "UserName";
                chkUsers.DataBind();
                CheckboxsItems();
            }
        }
    }
}

private void CheckboxsItems()
{
    foreach (ListItem item in chkUsers.Items)
    {
        string values = item.Value.ToString();
        foreach (DataRow row in dt.Rows)
        {
            string id = row["UserName"].ToString();
            string status = row["Status"].ToString();

            if (values == id && status.ToUpper() == "TRUE")
            {
                item.Selected = true;
            }
        }
    }
}

protected void OnUpdate(object sender, EventArgs e)
{
    foreach (ListItem item in chkUsers.Items)
    {
        if (item.Selected)
        {
            string id = item.Value.ToString();
            Update(id, "TRUE");
        }
        else
        {
            DataTable dt = (DataTable)ViewState["Data"];
            string id = item.Value.ToString();
            foreach (DataRow row in dt.Rows)
            {
                string values = row["UserName"].ToString();
                string status = row["Status"].ToString();
                if (values == id && status.ToUpper() != "")
                {
                    Update(id, "FALSE");
                }
                else if (values == id && status.ToUpper() == "")
                {
                    Update(id, DBNull.Value.ToString());
                }
            }
        }
    }
}

private void Update(string id, string status)
{
    string constring = ConfigurationManager.ConnectionStrings["Constring"].ToString();
    using (SqlConnection con = new SqlConnection(constring))
    {
        using (SqlCommand cmd = new SqlCommand("Update Category SET Status=@Status WHERE UserName='" + id + "'", con))
        {
            cmd.Parameters.AddWithValue("@Status", status);
            con.Open();
            cmd.ExecuteNonQuery();
            con.Close();
        }
    }
}

Screenshot