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c# - Eval check for DBNull doesnt work

<%# Eval("Description") == DBNull.Value ? "empty" : "notempty"%>

is showing always 'notempty' even there is null in that field in DB (type of varchar(), null) ... Tried also checking for empty string:

<%# Eval("Description") == "" ? "empty" : "notempty"%>

and it always displays notempty... what's wrong here??

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There is a difference between DBNull.Value and null. It is possible the field is returning null.

Try

<%# Eval("Description") == null ? "empty" : "notempty"%>

Also if the field value type is supposed to be string you could do something along the lines of..

<%# (Eval("Description") as string) ?? "empty" %>

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