Hey nauna,

Please refer below sample.

HTML

<asp:Panel ID="pnlCustomers" runat="server">
    <asp:ListView ID="lvCustomers" runat="server" GroupPlaceholderID="groupPlaceHolder1"
        ItemPlaceholderID="itemPlaceHolder1">
        <LayoutTemplate>
            <table>
                <tr>
                    <th>
                        CustomerId
                    </th>
                    <th>
                        ContactName
                    </th>
                    <th>
                        Country
                    </th>
                </tr>
                <asp:PlaceHolder runat="server" ID="groupPlaceHolder1"></asp:PlaceHolder>
            </table>
        </LayoutTemplate>
        <GroupTemplate>
            <tr>
                <asp:PlaceHolder runat="server" ID="itemPlaceHolder1"></asp:PlaceHolder>
            </tr>
        </GroupTemplate>
        <ItemTemplate>
            <td>
                <%# Eval("CustomerId") %>
            </td>
            <td>
                <%# Eval("ContactName") %>
            </td>
            <td>
                <%# Eval("Country") %>
            </td>
        </ItemTemplate>
    </asp:ListView>
</asp:Panel>
<asp:Button ID="btnExport" runat="server" Text="Export" OnClick="btnExport_Click" />

Namespaces

C#

using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.IO;
using iTextSharp.text;
using iTextSharp.text.html.simpleparser;
using iTextSharp.text.pdf;

VB.Net

Imports System.Data
Imports System.Data.SqlClient
Imports System.Configuration
Imports System.IO
Imports iTextSharp.text
Imports iTextSharp.text.html.simpleparser
Imports iTextSharp.text.pdf

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindListView();
    }
}

private void BindListView()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand())
        {
            cmd.CommandText = "SELECT TOP 10 CustomerId, ContactName, Country FROM Customers";
            cmd.Connection = con;
            using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
            {
                DataTable dt = new DataTable();
                sda.Fill(dt);
                lvCustomers.DataSource = dt;
                lvCustomers.DataBind();
            }
        }
    }
}

protected void btnExport_Click(object sender, EventArgs e)
{
    Response.ContentType = "application/pdf";
    Response.AddHeader("content-disposition", "attachment;filename=Panel.pdf");
    Response.Cache.SetCacheability(HttpCacheability.NoCache);
    StringWriter sw = new StringWriter();
    HtmlTextWriter hw = new HtmlTextWriter(sw);
    pnlCustomers.RenderControl(hw);
    StringReader sr = new StringReader(sw.ToString());
    Document pdfDoc = new Document(PageSize.A4, 10f, 10f, 100f, 0f);
    HTMLWorker htmlparser = new HTMLWorker(pdfDoc);
    PdfWriter.GetInstance(pdfDoc, Response.OutputStream);
    pdfDoc.Open();
    htmlparser.Parse(sr);
    pdfDoc.Close();
    Response.Write(pdfDoc);
    Response.End();
}

VB.Net

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Me.BindListView()
    End If
End Sub

Private Sub BindListView()
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As New SqlConnection(constr)
        Using cmd As New SqlCommand()
            cmd.CommandText = "SELECT TOP 10 CustomerId, ContactName, Country FROM Customers"
            cmd.Connection = con
            Using sda As New SqlDataAdapter(cmd)
                Dim dt As New DataTable()
                sda.Fill(dt)
                lvCustomers.DataSource = dt
                lvCustomers.DataBind()
            End Using
        End Using
    End Using
End Sub

Protected Sub btnExport_Click(ByVal sender As Object, ByVal e As EventArgs)
    Response.ContentType = "application/pdf"
    Response.AddHeader("content-disposition", "attachment;filename=Panel.pdf")
    Response.Cache.SetCacheability(HttpCacheability.NoCache)
    Dim sw As StringWriter = New StringWriter()
    Dim hw As HtmlTextWriter = New HtmlTextWriter(sw)
    pnlCustomers.RenderControl(hw)
    Dim sr As StringReader = New StringReader(sw.ToString())
    Dim pdfDoc As Document = New Document(PageSize.A4, 10.0F, 10.0F, 100.0F, 0.0F)
    Dim htmlparser As HTMLWorker = New HTMLWorker(pdfDoc)
    PdfWriter.GetInstance(pdfDoc, Response.OutputStream)
    pdfDoc.Open()
    htmlparser.Parse(sr)
    pdfDoc.Close()
    Response.Write(pdfDoc)
    Response.End()
End Sub

Screenshot

Listview

PDF