Open (Show) Base64 PDF data in new window (Tab) using C# and VB.Net in ASP.Net

Hi namojainashis...,

In order to dispalay base64 string as pdf in new tab use Javascript.

Check the example.

For this example i have used database to fetch the base64 string.

Once you got the base64 string you need to convert it to byte array and display the byte array as pdf in new tab.

HTML

<asp:Button Text="Display PDF" runat="server" OnClick="OnView" />

Namespaces

C#

using System.Data.SqlClient;
using System.Text;

VB.Net

Imports System.Data.SqlClient
Imports System.Text

Code

Default

C#

protected void OnView(object sender, EventArgs e)
{
    string base64String = "";
    string conString = "Server=.;DataBase=Test;Integrated Security=true";
    string query = "SELECT Data FROM tblFiles WHERE ID = 1";
    using (SqlConnection con = new SqlConnection(conString))
    {
        using (SqlCommand cmd = new SqlCommand(query))
        {
            cmd.Connection = con;
            con.Open();
            base64String = Convert.ToBase64String((byte[])cmd.ExecuteScalar());
            con.Close();
        }
    }

    Session["Base64String"] = base64String;
    string url = "PopUp.aspx";
    StringBuilder sb = new StringBuilder();
    sb.Append("<script type = 'text/javascript'>");
    sb.Append("window.open('");
    sb.Append(url);
    sb.Append("');");
    sb.Append("</script>");
    ClientScript.RegisterStartupScript(this.GetType(), "script", sb.ToString());
}

VB.Net

Protected Sub OnView(ByVal sender As Object, ByVal e As EventArgs)
    Dim base64String As String = ""
    Dim conString As String = "Server=.;DataBase=Test;Integrated Security=true"
    Dim query As String = "SELECT Data FROM tblFiles WHERE ID = 1"
    Using con As SqlConnection = New SqlConnection(conString)

        Using cmd As SqlCommand = New SqlCommand(query)
            cmd.Connection = con
            con.Open()
            base64String = Convert.ToBase64String(CType(cmd.ExecuteScalar(), Byte()))
            con.Close()
        End Using
    End Using

    Session("Base64String") = base64String
    Dim url As String = "PopUp.aspx"
    Dim sb As StringBuilder = New StringBuilder()
    sb.Append("<script type = 'text/javascript'>")
    sb.Append("window.open('")
    sb.Append(url)
    sb.Append("');")
    sb.Append("</script>")
    ClientScript.RegisterStartupScript(Me.GetType(), "script", sb.ToString())
End Sub

PopUp

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (Session["Base64String"] != null)
    {
        byte[] bytes = Convert.FromBase64String(Session["Base64String"].ToString());
        Response.Clear();
        Response.ContentType = "application/pdf";
        Response.Buffer = true;
        Response.Cache.SetCacheability(HttpCacheability.NoCache);
        Response.BinaryWrite(bytes);
        Response.End();
        Response.Close();
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Session("Base64String") IsNot Nothing Then
        Dim bytes As Byte() = Convert.FromBase64String(Session("Base64String").ToString())
        Response.Clear()
        Response.ContentType = "application/pdf"
        Response.Buffer = True
        Response.Cache.SetCacheability(HttpCacheability.NoCache)
        Response.BinaryWrite(bytes)
        Response.End()
        Response.Close()
    End If
End Sub

Screenshot