visual C#, Crystal reporting, unbound field

Hi Friends,

I am developing a windows application using C# in VS 2008, now i am creating a Crystal report with unbound field and pass a string value at runtime. now the issue is when I type string directly as shown below it shows report properly :

rpt.DataDefinition.FormulaFields["ubsPatientName"].Text = "\"some text to show\"";

but when I pass a value of datarow as given below it never show anything

DataRow dr = dsTemp.Tables["PatientById"].Rows[0];
rpt.DataDefinition.FormulaFields["ubsPatientName"].Text = dr["FirstName"].ToString();

I think its just because of "\" character which is not present in second case, but I don't exactly know the purpose of "\" and how to add this to string. please guide.

thanks.