How To Open PDF Files In New Tab In Browser Using GridView Row Command In ASP.NET C#

Question

i am trying to open PDF file in new Tab in browser, but its open same Tab.. iam using gridview Template field to open pdf..

ASP.NET

<asp:GridView ID="gvwPDF" runat="server" CssClass="mGrid" CellPadding="20" CellSpacing="20" AutoGenerateColumns="false" EmptyDataText="No files uploaded" Width="100%">
   <Columns>
     <asp:BoundField DataField="Text" HeaderText="File Name" />
    <asp:TemplateField>
         <ItemTemplate>
           <asp:LinkButton ID="lnkRead" runat="server" Text="✉ Read" CommandName="Read" CssClass="gvwedit" ForeColor="Green" OnClick="ReadPDFFile" CommandArgument='<%# Eval("Value") %>'></asp:LinkButton>
           </ItemTemplate>
         </asp:TemplateField>
</Columns>
 </asp:GridView>

C#

protected void Page_Load(object sender, EventArgs e)
    {
        try
        {
            if (!IsPostBack)
            {
                string[] filePaths = Directory.GetFiles(Server.MapPath("~/Uploads/"));
                List<ListItem> files = new List<ListItem>();
                foreach (string filePath in filePaths)
                {
                    files.Add(new ListItem(Path.GetFileName(filePath), filePath));
                }
                gvwPDF.DataSource = files;
                gvwPDF.DataBind();
            }
        }
        catch (Exception ex)
        {
            //PopMsg.Pop(ex.Message.ToString(), BmGate.WebFormUserControls.Common.MessageBox.IconError, "Error");
            ScriptManager.RegisterStartupScript(this, GetType(), "Error Message", "alert('" + ex.Message.ToString() + "')", true);
        }
    }

protected void ReadPDFFile(object sender, EventArgs e)
    {
        try
        {
            string path = (sender as LinkButton).CommandArgument;
            WebClient client = new WebClient();
            Byte[] buffer = client.DownloadData(path);

            if (buffer != null)
            {
                Response.ContentType = "application/pdf";
                Response.AddHeader("content-length", buffer.Length.ToString());
                Response.BinaryWrite(buffer);
                ClientScript.RegisterClientScriptBlock(this.GetType(), "Message", "window.open('application/pdf','_blank');", true);
            }
        }
        catch (Exception ex)
        {
            ScriptManager.RegisterStartupScript(this, GetType(), "Error Message", "alert('" + ex.Message.ToString() + "')", true);
        }
    }

help to solve this issue..

score 3 · Accepted Answer · edited May 23 '17 at 12:00

In your LinkButton, set the OnClientClick to this:

<asp:LinkButton ID="lnkRead" runat="server" Text="✉ Read" CommandName="Read" CssClass="gvwedit" ForeColor="Green" OnClientClick="window.open('newPage.aspx?fileName=<%# Eval("Value") %>', '_newtab');"></asp:LinkButton>

This will open a new tab with the PDF file name as a QueryString (Other solutions for opening new tabs here). What you would want to change in your current Page_Load is making the value of the ListItem the file name so that you are not passing a file path over URL parameter.

In the Page_Load of newPage.aspx (the new tab being opened), load your pdf data. If you are receiving a Byte[] from your WebClient, this is how I write the PDF:

string fileName = Request.QueryString["fileName"];
string path = Path.Combine(Server.MapPath("~/Uploads/"), fileName);
WebClient client = new WebClient();
Byte[] buffer = client.DownloadData(path);
HttpContext.Current.Response.Clear();
HttpContext.Current.Response.AddHeader("Content-Type", "application/pdf");
HttpContext.Current.Response.AddHeader("Content-Disposition", "inline; filename=" + fileName);
HttpContext.Current.Response.BinaryWrite(buffer);
HttpContext.Current.Response.End();

Let me know if this works for you. I've tested the OnClientClick in the LinkButton and it opened a new tab successfully. Separately, I've used the Response code above in a few different pages without issue.

score 0 · Answer 2 · answered Jan 29 '16 at 10:19

I see you are already trying to set the target to _blank, but not until the PDF is being constructed, which is too late. It has to be done in the page that has the LinkButtons.

Try using the GridView_RowDataBound event of gvwPDF to modify the LinkButtons, something like this:

var linkButton = e.Row.FindControl("lnkRead");
linkButton.Attributes.Add("target", "_blank");

score -1 · Answer 3 · answered Jan 29 '16 at 09:15

-1

Try to add a content-disposition header:

Response.AddHeader("content-disposition", "attachment;filename=sample1.pdf");

answered Jan 29 '16 at 09:15

bdn02

1,500
9
15

try 'Response.AddHeader("content-disposition", "inline;filename=sample1.pdf");' – bdn02 Jan 29 '16 at 09:37
This does nothing to open an attachment into a new tab as the OP requests. – Bonez024 May 02 '18 at 13:24

How To Open PDF Files In New Tab In Browser Using GridView Row Command In ASP.NET C#

3 Answers3