threw an exception of type system nullreferenceexception c#

Question

Hello,

 

I am use repeater control and i that i have a label so i am assign value to this label in code behind but system gives error threw an exception of type system nullreferenceexception c#

 

This is my aspx code

<asp:Repeater ID="Repeater1" runat="server">
<HeaderTemplate>
<table>
</HeaderTemplate>
<ItemTemplate>
<tr>
<td>
<asp:Label ID="lbldata" runat="server"></asp:Label>
</td>
</tr>
</ItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:Repeater>

And this is Code behind:-

DataTable dt_OwnerFilter = new DataTable();
Label r1 = (Label)Page.FindControl("lbldata");
dt_OwnerFilter = bl.BL_FetchOwnerInfo(bo);
pgsource.DataSource = dt_OwnerFilter.DefaultView;
lblfetchdata.Text = string.Empty;
int i = 1;
foreach (DataRow dRow in dt_OwnerFilter.Rows)
{
if (dt_OwnerFilter.Rows.Count > 0)
{
string htmlcode = "";
htmlcode = "<a class='btn btn-primary' onclick='fnShow(" + dRow["PropertyDetailsId"] + ")'> " + i + "</a>";
r1.Text += htmlcode + "<br>"; //// Here is error
}
i = i + 1;
}