Add ASHX file to your solution and call this page 

bind each pdf id to each frame .

string bindtoFrame = "File.ashx?id=" + id.ToString();

public void ProcessRequest(HttpContext context)
{
string id = context.Request.QueryString["id"].ToString();

string sConn = System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString"].ToString();
SqlConnection objConn = new SqlConnection(sConn);
objConn.Open();
DataTable file = new DataTable();
SqlCommand cmd = objConn.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "SELECT * FROM [AttachmentTable] where ID = '"+ id +"'";
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(file);

objConn.Close();
cmd.Dispose();

if (file.Rows.Count > 0)
{
DataRow row = file.Rows[0];
string name = (string)row["Filename"];
string contentType = (string)row["FileExt"];
Byte[] data = (Byte[])row["Attachment"];
int FileSize = Convert.ToInt32(row["Filesize"].ToString());

//Send the file to the browser
context.Response.AddHeader("Content-type", "application/pdf");
context.Response.AddHeader("Content- Disposition", "attachment; filename=" + name);
context.Response.OutputStream.Write(data, 0, FileSize);
context.Response.Flush();
context.Response.End();
}
}

Hi kats9993,

I have created sample code by refering the below article which full-fill your requirement.

Convert Binary data to PDF file in C# and VB.Net

HTML

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" OnRowDataBound="GridView1_RowDataBound">
    <Columns>
        <asp:BoundField DataField="Id" HeaderText="File Id" />
        <asp:BoundField DataField="Name" HeaderText="File Name" />
        <asp:TemplateField ItemStyle-HorizontalAlign="Center">
            <ItemTemplate>
                <asp:Literal ID="ltEmbed" runat="server" />
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        this.BindGrid();
    }
}
private void BindGrid()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand())
        {
            cmd.CommandText = "SELECT  *  FROM tblFiles";
            cmd.Connection = con;
            con.Open();
            GridView1.DataSource = cmd.ExecuteReader();
            GridView1.DataBind();
            con.Close();
        }
    }
}

protected void Upload(object sender, EventArgs e)
{
    string filename = Path.GetFileName(FileUpload1.PostedFile.FileName);
    string contentType = FileUpload1.PostedFile.ContentType;
    using (Stream fs = FileUpload1.PostedFile.InputStream)
    {
        using (BinaryReader br = new BinaryReader(fs))
        {
            byte[] bytes = br.ReadBytes((Int32)fs.Length);
            string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
            using (SqlConnection con = new SqlConnection(constr))
            {
                string query = "insert into tblFiles values (@Name, @ContentType, @Data)";
                using (SqlCommand cmd = new SqlCommand(query))
                {
                    cmd.Connection = con;
                    cmd.Parameters.AddWithValue("@Name", filename);
                    cmd.Parameters.AddWithValue("@ContentType", contentType);
                    cmd.Parameters.AddWithValue("@Data", bytes);
                    con.Open();
                    cmd.ExecuteNonQuery();
                    con.Close();
                }
            }
        }
    }
    Response.Redirect(Request.Url.AbsoluteUri);
}

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        string embed = "<object data=\"{0}{1}\" type=\"application/pdf\" width=\"300px\" height=\"200px\">";
        embed += "If you are unable to view file, you can download from <a href = \"{0}{1}&download=1\">here</a>";
        embed += " or download <a target = \"_blank\" href = \"http://get.adobe.com/reader/\">Adobe PDF Reader</a> to view the file.";
        embed += "</object>";
        int fileId = Convert.ToInt32(e.Row.Cells[0].Text);
        (e.Row.FindControl("ltEmbed") as Literal).Text = string.Format(embed, ResolveUrl("~/FileCS.ashx?Id="), fileId);
    }
}

FileCs.ashx Handler

<%@ WebHandler Language="C#" Class="FileCS" %>

using System;
using System.Web;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
public class FileCS : IHttpHandler
{
    public void ProcessRequest(HttpContext context)
    {
        int id = int.Parse(context.Request.QueryString["Id"]);
        byte[] bytes;
        string fileName, contentType;
        string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
        using (SqlConnection con = new SqlConnection(constr))
        {
            using (SqlCommand cmd = new SqlCommand())
            {
                cmd.CommandText = "SELECT Name, Data, ContentType FROM tblFiles WHERE Id=@Id";
                cmd.Parameters.AddWithValue("@Id", id);
                cmd.Connection = con;
                con.Open();
                using (SqlDataReader sdr = cmd.ExecuteReader())
                {
                    sdr.Read();
                    bytes = (byte[])sdr["Data"];
                    contentType = sdr["ContentType"].ToString();
                    fileName = sdr["Name"].ToString();
                }
                con.Close();
            }
        }

        context.Response.Buffer = true;
        context.Response.Charset = "";
        if (context.Request.QueryString["download"] == "1")
        {
            context.Response.AppendHeader("Content-Disposition", "attachment; filename=" + fileName);
        }
        context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
        context.Response.ContentType = "application/pdf";
        context.Response.BinaryWrite(bytes);
        context.Response.Flush();
        context.Response.End();
    }

    public bool IsReusable
    {
        get
        {
            return false;
        }
    }
}

 Screenshot