Error in unintuitive place reading in DataList [closed]

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***ERROR***
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Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
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Line: <td>< asp:Label ID="Label59" runat="server" Text='<%# Eval("field2").Equals("") ? "" : Eval("field3") + " " + Eval("field4") + " " + Eval("field 5") %>' /></td>
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Hi,

Appreciate being able to get any feedback. I'm somewhat new to ASP.NET using 3.5

Getting error after adding a new field to an existing sqlreader class. The error is supposedly pointing to a null value in a datalist. But if this one line is removed there is no problem for the entire ItemTemplate.

_var= reader["field"] != null ? (int)reader["field"] : 0;

The only other change to the sqlreader class is the new field's get set.

Thank you in advance

Answer 1

If your field2 contains null, Eval("field2") will be null so you'll get a null-ref while calling Equals on it. Simply swap the operands:

<%# "".Equals(Eval("field2")) ? "" : Eval("field3") + " " + Eval("field4") + " " + Eval("field 5") %>

Although I'd recommend comparing with null which is more readable and likely more correct.