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System.NullReferenceException: Object reference not set to an instance of an object.

Question
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When using the Is Nothing command below I get the error seen below.
System.NullReferenceException: Object reference not set to an instance of an object.
I would appreciate any suggestions. Basically when the MapPhoto label is empty I would like the hyperlink to be invisible.
<asp:TemplateField HeaderText="Map Photo" HeaderStyle-HorizontalAlign="Left" ItemStyle-VerticalAlign="Middle" ItemStyle-Width="10%"> <ItemTemplate> <p style="margin- padding: 0px 10px 0px 5px;"> <asp:Label ID="MapPhoto" runat="server" Text='<%# Eval("PHOTO2") %>'></asp:Label> <asp:HyperLink class="popup" runat="server" ID="ViewPhoto2" NavigateUrl="#" Style="text-decoration: underline;">View Photo 2<span><img src='/user_images/<%# Eval("PHOTO2")%>'></span></asp:HyperLink> </p> </ItemTemplate> </asp:TemplateField>
Protected Sub GridView1_RowDataBound(sender As Object, e As GridViewRowEventArgs) Dim MapPhoto As Label = DirectCast(e.Row.FindControl("MapPhoto"), Label) Dim ViewPhoto2 As HyperLink = DirectCast(e.Row.FindControl("ViewPhoto2"), HyperLink) If MapPhoto.Text Is Nothing Then ViewPhoto2.Visible = False End If End Sub
- Changed type KareninstructorMVP Tuesday, April 10, 2018 3:38 PM This is a question
- Moved by Cherry BuMicrosoft contingent staff Tuesday, April 17, 2018 9:06 AM move from vb.net
Tuesday, April 10, 2018 3:16 PM
All replies
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The presentation part is not done here.
It is done in the forum
Mostly these kind are problems are caused because ASP.Net has no state and at post back everything is nothing.
In this case MapPhoto (the text can only be empty)
Success
Cor- Proposed as answer by KareninstructorMVP Tuesday, April 10, 2018 3:38 PM
Tuesday, April 10, 2018 3:26 PM -
You explained why I am having the problem but I don't really see a resolution. Can you help of not?Wednesday, April 11, 2018 2:45 PM
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Never mind the last reply as I found another way to do this through the asp:Templatefield as seen below through "Visible" property of the asp:Hyperlink:
<asp:TemplateField HeaderText="Map Photo" HeaderStyle-HorizontalAlign="Left" ItemStyle-VerticalAlign="Middle" ItemStyle-Width="10%"> <ItemTemplate> <p style="margin-top: -10px; padding: 0px 10px 0px 5px;"> <asp:Label ID="MapPhoto" runat="server" Text='<%# Eval("PHOTO2") %>'></asp:Label> <asp:HyperLink ID="ViewPhoto2" class="popup" href="#" Style="text-decoration: underline;" runat="server" Visible='<%# Not String.IsNullOrEmpty(Convert.ToString(Eval("PHOTO2"))) %>'>View Photo 2<span><img src='/user_images/<%# Eval("PHOTO2")%>'></span></asp:HyperLink> </p> </ItemTemplate> </asp:TemplateField>
Wednesday, April 11, 2018 3:35 PM