Open Word and PDF files in browser window using C# in ASP.Net

<tr>
   <td>Attach Resume</td>
   <td>Maximum file size is 300 KB<br /><asp:FileUpload ID="upResume" runat="server" Height="22px" Width="324px"/></td>
   <td><asp:Label ID="lblResume" runat="server"></asp:Label></td>
   <td><asp:LinkButton ID="btnview" runat="server" CommandName="view" Text="View" OnClientClick="btnView_Click"/></td>        
</tr>

Hi, I want to ask. How to write coding for view or read file that already uploaded in doc/docx and pdf format. I want to put a link button which is "view" to open the file. Do I need to set each of the format? Kindly help me or please advise me some suggestion. Thank you.