What is the best way of rewriting these (erroneous) lines?
bool? result = dr["result"] == DBNull.Value ? null : Convert.ToInt32(dr["result"]);
...and...
dr["result"] = result ?? DBNull.Value;
Both do not compile.
I am using the MySql connector and it doesn't let me set, for example, dr["result"] = null;
which is what I first tried.
Is there an mor开发者_C百科e suitable .NET data type for representing a MySql nullable tinyint(1)
?
How about:
dr["Hello"] = (object)result ?? DBNull.Value;
bool? result = dr["result"] == DBNull.Value ? null : (bool?)(Convert.ToInt32(dr["result"]) != 0);
The reason your suggestion does not compile is that both alternatives of the ternary operator ?:
must have the same type. DBNull.Value
obviously is not the same type as a bool?
. Casting the bool?
to an object
however makes them both the same type. Similar rules apply on the second row.
If you are using a stored procedure or SQL queries then you can use ISNULL()
function of SQL to handle NULL...
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