ASP.NET

<div class="col-md-3">
                       
                <label class="switch2">
                <input class="switch-input2" type="checkbox" id="contractselection" name="contractselection" runat="server"/>
                  
                  
             </label>            
          </div>
          <div class="col-xs-4">  
           
            <div class="contractrow">                  
            <label for="exampleInputCity">Contract:*:</label>
             <asp:TextBox ID="contractnumber" class="form-control" name="contractnumber" placeholder="" runat="server"></asp:TextBox>           
            </div>  
             <asp:RequiredFieldValidator ID="rfvcontractnumber"    runat="server" ControlToValidate ="contractnumber"   ErrorMessage="Please enter a Contract">   
                </asp:RequiredFieldValidator>           
             <div class="orderrow">                  
            <label for="exampleInputCity">Solicitation:*:</label>
             <asp:TextBox ID="ordernumber" class="form-control" name="ordernumber" placeholder="" runat="server"></asp:TextBox>           
            </div> 
             <asp:RequiredFieldValidator ID="rfvsolicitationnumber"    runat="server" ControlToValidate ="ordernumber"   ErrorMessage="Please enter a Order">   
                </asp:RequiredFieldValidator>                
             </div>   
          </div>
          </div>       

<script type="text/javascript">
    $(function () {
        $(".contractrow").show();
        $(".switch-input2").click(function () {
            if ($(this).is(":checked")) {
                $(".contractrow").show();
            } else {
                $(".solicitationrow").hide();
            }
        });
    });
</script>

<label class="switch">
	<input class="switch-input" type="checkbox" id="orderselection" name="orderselection" runat="server" />
	 
	 
</label>

<label for="exampleOrderNumber">Are Redelegations Authorized?<label for="exampleInputCity">:</label>           
             <label class="switch">
                <input class="switch-input" type="checkbox" id="authredelegation" name="authredelegation" runat="server" />
                  
                  
             </label>

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load

        Dim table As New DataTable()
        Using con = New SqlConnection(ConfigurationManager.ConnectionStrings("PersonnelPolicyDB").ConnectionString)
            Using cmd = New SqlCommand("usp_AddABCD", con)
                Using da = New SqlDataAdapter(cmd)
                    cmd.CommandType = CommandType.StoredProcedure
                    cmd.Parameters.AddWithValue("@oderno", "orderno.text")
                    cmd.Parameters.AddWithValue("@orderdate", "orderdate.text")
                    da.Fill(table)
                End Using
            End Using
        End Using
      End Sub



        Dim table As New DataTable()
        Using con = New SqlConnection(ConfigurationManager.ConnectionStrings("PersonnelPolicyDB").ConnectionString)
            Using cmd = New SqlCommand("usp_GetABCD", con)
                Using da = New SqlDataAdapter(cmd)
                    cmd.CommandType = CommandType.StoredProcedure
                    cmd.Parameters.AddWithValue("@orderno", "orderno.text")
                   da.Fill(table)
                End Using
            End Using
        End Using
    End Sub
        
       Private Sub SendPDFEmail(dt As DataTable)
           Using sw As New StringWriter()
               Using hw As New HtmlTextWriter(sw)
                   Dim companyName As String = "my Company"
                   Dim orderNo As Integer = 2303
                   Dim sb As New StringBuilder()
                   sb.Append("<table width='100%' cellspacing='0' cellpadding='2'>")
                   sb.Append("<tr><td align='center' style='background-color: #18B5F0' colspan = '2'>Order Sheet</td></tr>")
                   sb.Append("<tr><td colspan = '2'></td></tr>")
                   sb.Append("<tr><td>Order No:")
                   sb.Append(orderNo)
                   sb.Append("</td><td>Date: ")
                   sb.Append(DateTime.Now)
                   sb.Append(" </td></tr>")
                   sb.Append("<tr><td colspan = '2'>Company Name : ")
                   sb.Append(companyName)
                   sb.Append("</td></tr>")
                   sb.Append("</table>")
                   sb.Append("<br />")
                   sb.Append("<table border = '1'>")
                   sb.Append("<tr>")
                   For Each column As DataColumn In dt.Columns
                       sb.Append("<th style = 'background-color: #D20B0C;color:#ffffff'>")
                       sb.Append(column.ColumnName)
                       sb.Append("</th>")
                   Next
                   sb.Append("</tr>")
                   For Each row As DataRow In dt.Rows
                       sb.Append("<tr>")
                       For Each column As DataColumn In dt.Columns
                           sb.Append("<td>")
                           sb.Append(row(column))
                           sb.Append("</td>")
                       Next
                       sb.Append("</tr>")
                   Next
                   sb.Append("</table>")
                   Dim sr As New StringReader(sb.ToString())
   
                   Dim pdfDoc As New Document(PageSize.A4, 10.0F, 10.0F, 10.0F, 0.0F)
                   Dim htmlparser As New HTMLWorker(pdfDoc)
                   Using memoryStream As New MemoryStream()
                       Dim writer As PdfWriter = PdfWriter.GetInstance(pdfDoc, memoryStream)
                       pdfDoc.Open()
                       htmlparser.Parse(sr)
                       pdfDoc.Close()
                       Dim bytes As Byte() = memoryStream.ToArray()
                       memoryStream.Close()
   
                       Dim mm As New MailMessage("NoReply@domain.com", "myemail@domain.com")
                       mm.Subject = "iTextSharp PDF"
                       mm.Body = "iTextSharp PDF Attachment"
                       mm.Attachments.Add(New Attachment(New MemoryStream(bytes), "iTextSharpPDF.pdf"))
                       mm.IsBodyHtml = True
                       Dim smtp As New SmtpClient()
                       smtp.Host = "myhostname"
                       smtp.EnableSsl = False
                       Dim NetworkCred As New System.Net.NetworkCredential()
                       NetworkCred.UserName = "myusername"
                       NetworkCred.Password = "mypassword"
                       smtp.UseDefaultCredentials = True
                       smtp.Credentials = NetworkCred
                       smtp.Port = 25
                       smtp.Send(mm)
                   End Using
               End Using
           End Using
    End Sub

public ActionResult Index ()
         {
             CatalogModel m = new CatalogModel ();
             m.LocalCodeColumn = 1;
             m.PriceColumn = 2;
             m.SelectedClientList = m.GetClientSelectedItems ();
             return View (m);
         }

Select Client: @ Html.DropDownListFor (m => m.SelectedClientList, Model.GetClientSelectedItems (), "--Select--", new {@id = "ddlClient"})

public IEnumerable<SelectListItem> GetClientSelectedItems()
        {
            // Function GetListClient() return IEnumerable<SelectListItem> 
            IEnumerable<SelectListItem> listClient = dataServices.GetClients();
            return listClient;
        }