C#

protected void Page_PreRender(object sender, EventArgs e)
  {
    DataTable dt = new DataTable("INFO");
    dt.Columns.Add("url", typeof(string));

    string[] fileEntries = Directory.GetFiles(Server.MapPath("~/Documents/"));

    dt.Rows.Add("~/Documents/" + Path.GetFileName(fileName));

    grid.DataSource = dt;
    grid.DataBind();
  }

<a href="~/Documents/" + Path.GetFileName(fileName)"> DOWNLOAD </a>

// KeyValuePair declarations
private KeyValuePair<Type, object> Kvp1 = new KeyValuePair<Type, object> (typeof(int), 199);
private KeyValuePair<Type, dynamic> Kvp2 = new KeyValuePair<Type, dynamic>(typeof(int), 199);

// Tuple declarations
private Tuple&lt;Type, object&gt; twoTuple1 = new Tuple&lt;Type, object&gt;(typeof(int), 199);
private Tuple&lt;Type, dynamic&gt; twoTuple2 = new Tuple&lt;Type, dynamic&gt;(typeof(int), 199);

// List<dynamic> declaration
private List&lt;dynamic&gt; dyList = new List&lt;dynamic&gt;();

// method that demonstrates use of declared objects above
private void TestDynamicVsNonDynamic()
{
    // using KeyValuePair

    //int a = Kvp1.Value + 1;      // will not compile
    int b = Kvp2.Value + 1;        // will compile, give expected result

    // using Tuple

    //int x = twoTuple1.Item2 + 1; // will not compile
    int y = twoTuple2.Item2 + 1;   // will compile, give expected result

    // using List<dynamic>

    dyList.Add(199);                // will compile    

    dyList.Add(new TextBox{Text = "some text&"});

    int z = dyList[0] + 1;          // will compile, give expected result

    dyList[1].Text += " ... blah, blah blah";

    string s = dyList[1].Text;      // will compile, give expected result

    Type dyList1Type = dyList[1].GetType(); // returns expected Type: TextBox

}