Hi,

I have a calculated field within a TypedList I wish to display. I went through this link: http://llblgen.com/TinyForum/Messages.aspx?ThreadID=8110&StartAtMessage=0&#62541 and it works great!

I'm concatenating 2 fields (ResourceFields.Title and ResourceFields.Showname) as follows:

IExpression myTest = new Expression( 
       new Expression( ResourceFields.Title, ExOp.Add, " - "),
         ExOp.Add, ResourceFields.Showname);
fields.DefineField(new EntityField2("FullTitle", myTest2), index);

To make this a bit tidier, I'd really like to do is examine the ResourceFields.Showname value, and if its null/empty, not display the "-" at all.

What is the best way to do this?

You could include a CASE plus ISNULL DBFunctionCall expression to the formula:

DbFunctionCall dashShowname = new DbFunctionCall("CASE ISNULL({0}, '') WHEN '' THEN '' ELSE ' - ' + {1} END", 
     new object[]{ ResourceFields.Showname, ResourceFields.Showname});

IExpression myTest = new Expression( ResourceFields.Title, ExOp.Add, dashShowname);

fields.DefineField(new EntityField2("FullTitle", myTest2), index);

Thanks David that worked perfectly.. yet another cool feature I've learnt about!