Store and View PDF Files in a GridView

Look at the following procedure.

Step 1: Database Structure.

Query

Create a table named tbl_pdf.



WebConfig



Upload.aspx Code

<asp:FileUpload ID="”FileUpload”" runat=”server” /> <asp:Button ID="”btnsubmit”" runat=”server” Text=”Upload”  />
<asp:Button ID="”btncancel”" runat=”server” Text=”Cancel” /> <asp:Label ID="”alert”" runat=”server”></asp:Label>
<asp:GridView ID="”GridView1″" runat=”server” /> <asp:Label ID="”Label1″" runat=”server”></asp:Label>

Screen



Upload.aspx.cs

Step 2: Storing PDF files into database.

Source Code

protected void btnsubmit_Click(object sender, EventArgs e)
{
   try
   {
      byte[] pdf = null;
      if(FileUpload.HasFile & FileUpload.PostedFile != null)
      {
         HttpPostedFile file = FileUpload.PostedFile;
         pdf = new byte[file.ContentLength];
         file.InputStream.Read(pdf, 0, file.ContentLength);
      }
      SqlConnection con = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings[“userconnstring”].ConnectionString);
      SqlCommand cmd = new SqlCommand(“insert into tbl_pdf ([Document],[DocumentName]) values (@Document,@DocumentName)”, con);
con.Open();
      cmd.Parameters.AddWithValue(“@DocumentName”, FileUpload.PostedFile.FileName);
      cmd.Parameters.AddWithValue(“@Document”, pdf);
      cmd.ExecuteNonQuery();
      alert.Text = “Document Uploaded Successfully”;
      con.Close();
   }
   catch(Exception ex)
   {
      throw ex;
   }
}

Gridview.aspx

<asp:GridView ID=”GridView1″ runat=”server” />

Step 3: Bind data into the GridView using a simple datasource connection.

Screen



After binding a GridView looks like this.

<asp:GridView ID="”GridView1″" runat=”server” AutoGenerateColumns=”False” DataSourceID=”PDFViewer” EnableModelValidation=”True”>
<Columns>
<asp:BoundField DataField=”Doc_ID” HeaderText=”ID” SortExpression=”Doc_ID” />
<asp:BoundField DataField=”DocumentName” HeaderText=”DocumentName” SortExpression=”DocumentName” />
<asp:TemplateField ItemStyle-HorizontalAlign=”Center” >
<ItemTemplate>
<asp:LinkButton ID="”lnkView”" runat=”server” Text=”View” OnClick=”View” CommandArgument='<%# Eval(“Doc_ID”) %>’></asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="”PDFViewer”" runat=”server” ConnectionString=”<%$ ConnectionStrings:WordpressConnectionString %>” SelectCommand=”SELECT [Doc_ID],[DocumentName] FROM [tbl_pdf]”></asp:SqlDataSource>

Step 4: Now create a Generic Handler to view PDF in a GridView and create a new handler in ASP.Net as in the following:



Pdfhandler.ashx.cs Code:[Full] 

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.IO;
using System.Linq;
using System.Web;
namespace MyApplication
{
   /// <summary>
   /// Summary description for ImageViewer
   /// </summary>
   public class ImageViewer : IHttpHandler
   {
      public void ProcessRequest(HttpContext context)
      {
         Int32 theID;
         if (context.Request.QueryString[“id”] != null)
         theID = Convert.ToInt32(context.Request.QueryString[“id”]);
         else
         throw new ArgumentException(“No parameter specified”);
         context.Response.ContentType = “Application/pdf”;
         Stream strm = DisplayImage(theID);
         byte[] buffer = new byte[2048];
         int byteSeq = strm.Read(buffer, 0, 2048);
         while (byteSeq > 0)
         {
            context.Response.OutputStream.Write(buffer, 0, byteSeq);
            byteSeq = strm.Read(buffer, 0, 2048);
         }
      }
      public Stream DisplayImage(int theID)
      {
         string str = “Data Source=.;Initial Catalog=Wordpress;Integrated Security=True”;
         SqlConnection connection = new SqlConnection(str);
         string sql = “SELECT Document FROM tbl_pdf WHERE Doc_ID = @Doc_ID”;
         SqlCommand cmd = new SqlCommand(sql, connection);
         cmd.CommandType = CommandType.Text;
         cmd.Parameters.AddWithValue(“@Doc_ID”, theID);
         connection.Open();
         object theImg = cmd.ExecuteScalar();
         try
         {
            return new MemoryStream((byte[])theImg);
         }
         catch
         {
            return null;
         }
         finally
         {
            connection.Close();
         }
      }
      public bool IsReusable
      {
         get
         {
            return false;
         }
      }
   }
}

Step 5: In the next step add a linkbutton in GridView to view the PDF Files from the database:

<asp:TemplateField ItemStyle-HorizontalAlign=”Center” > <ItemTemplate> <asp:LinkButton ID=”lnkView” runat=”server” Text=”View” OnClick=”View” CommandArgument='<%# Eval(“Doc_ID”) %>’></asp:LinkButton> </ItemTemplate> </asp:TemplateField> </Columns> </asp:GridView>

Step 6: Create a OnClick view function behind the upload.aspx.cs and call the Generic handler here.

Code 

protected void View(object sender, EventArgs e)
{
   int id = int.Parse((sender as LinkButton).CommandArgument);
   string embed = “”;
   embed += “If you are unable to view file, you can download from here“;
   embed += ” or download Adobe PDF Reader to view the file.”;
   embed += “”;
   Label1.Text = string.Format(embed, ResolveUrl(“~/Pdfhandler.ashx?Id=”), id);
}

Output