Add the client' selected filename and it's path into a listbox.

Dear All, Can any of you provide a code fragment to solve the following problem? - I want to create a ASP.NET page, consist with 1 button and 1 ListBox. - When I click on the button, it will open a OpenFileDialog, which list the files in Client's computer. (Not Server) - Once the user choose a file, the name of the file and it's path will be added to the ListBox. - And if the user click the button and select a file again, it will add the name and path of the newly selected file into ListBox. I had try to use the following, but it does work at all. in MyPage.aspx

<input type="file" runat="server" onClick="Button_Submit">

and in the C# code behind....

protected void Button_Submit(System.Object sender, System.EventArgs e) 
{
  System.Web.HttpPostedFile UpFile = TestFile.PostedFile;
  int FileLength;
  FileLength = UpFile.ContentLength;
  ...
  ...
  ...
  // haven't finish yet. I was just wanting to see if it can get the size of the file
}

Thanks Very Much