How to populate and validate Dropdowncheckboxlist custom control in - ASPMANTRA | Asp.Net,MVC,AngularJs,Jquery,Javascript,Sql Server AND WCF snippets and tutorial

How to populate and validate Dropdowncheckboxlist custom control in

In this article I am going to explain how to populate and validate the Dropdowncheckbox custom control in

How to populate and validate Dropdowncheckboxlist custom control in

In previous article I have discuss about DLL of DROPDOWNCHCKBOXES. When you added the control to toolbox, you will saw 2 control dropdowncheckboxes and validate control named ExtendedRequiredfiledValidator.

How to populate and validate Dropdowncheckboxlist custom control in

I have created a table Tb_State and insert some dummy records.


Now add a webform to project. Drag and drop the dropdowncheckboxes and validator control from toolbox. When you place the control on webform you will saw register directive on webform:
<%@ Register Assembly="DropDownCheckBoxes" Namespace="Saplin.Controls" TagPrefix="asp" %>

If you want select all option, set  UseSelectAllNode option to true.

By default text is select, if want to change set as e.g. given below:
<Texts SelectBoxCaption="Select State" />

Here is the complete HTML markup of webform:

<html xmlns="">
<head id="Head1" runat="server">
    <title>Dropdown checkboxes Tutorial</title>
    <form id="form1" runat="server">
    <fieldset style="width:35%;height:160px">
    <legend>Example of Dropdown checkbox</legend>
    <tr><td>Select State :</td><td><asp:DropDownCheckBoxes ID="ddlcheckbox" runat="server"
            Width="180px" UseSelectAllNode="true" AutoPostBack="true">
        <Style SelectBoxWidth="200" DropDownBoxBoxWidth="160" DropDownBoxBoxHeight="100" />
        <Texts SelectBoxCaption="Select State" />        
        </asp:DropDownCheckBoxes></td><td><asp:ExtendedRequiredFieldValidator ID="ExtendedRequiredFieldValidator1" runat="server" ControlToValidate="ddlcheckbox" ErrorMessage="State Field is required" ForeColor="Red"></asp:ExtendedRequiredFieldValidator>
      <tr><td></td><td> <asp:Button ID="Button1" runat="server" Text="Button" /></td><td></td></tr>

Import the namespaces
C# code
using System.Data;
using System.Data.SqlClient;
using System.Configuration; Code
Imports System.Data
Imports System.Data.SqlClient
Imports System.Configuration

Populate dropdowncheckboxes
Create a method to bind the control and call it on page load.
C# code
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["connection"].ToString());
    DataTable dt = new DataTable();
    protected void Page_Load(object sender, EventArgs e)
        if (!IsPostBack)

    public void Bindstate()
        SqlDataAdapter adp = new SqlDataAdapter("select * from Tb_State", con);
        if (dt.Rows.Count > 0)
            ddlcheckbox.DataSource = dt;
            ddlcheckbox.DataTextField = "Statename";
            ddlcheckbox.DataValueField = "Id";
    } Code
Private con As New SqlConnection(ConfigurationManager.ConnectionStrings("connection").ToString())
    Private dt As New DataTable()
    Protected Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load
        If Not IsPostBack Then
        End If
    End Sub
    Public Sub Bindstate()
        Dim adp As New SqlDataAdapter("select * from Tb_State", con)
        If dt.Rows.Count > 0 Then
            ddlcheckbox.DataSource = dt
            ddlcheckbox.DataTextField = "Statename"
            ddlcheckbox.DataValueField = "Id"
        End If
    End Sub

Button click write the below given code:
C# code
protected void Button1_Click(object sender, EventArgs e)
            string statenames = string.Empty;
            foreach (ListItem item in ddlcheckbox.Items)
                if (item.Selected)
                    statenames += item.Text + "\\n";
            Response.Write("<script type=\"text/javascript\">alert('" + statenames + "');</script>");
        catch (Exception ex) { }
    } Code
    Protected Sub Button1_Click(sender As Object, e As System.EventArgs) Handles Button1.Click
            Dim statenames As String = String.Empty
            For Each item As ListItem In ddlcheckbox.Items
                If item.Selected Then
                    statenames += item.Text + "\n"
                End If
            Response.Write((Convert.ToString("<script type=""text/javascript"">alert('") & statenames) + "');</script>")
        Catch ex As Exception
        End Try
    End Sub
Now build and run the application. 

What do you think about this article?

If you found this article useful, please share and follow on Facebook, Twitter, Google Plus and other social media websites. To get free updates subscribe to newsletter. Please put your thoughts and feedback in comments section.