Q about conditional

[AP]

Why do I get a conversion error with this line of code? (Type of conditional
expression can't be determined because there is no implicit conversion
between 'int' and 'System.DBNull')
object o = (1+2 ==3) ? 3 : DBNull.Value;

when

object o;

if (1+2==3) {

o = 3;

else {

o = DBNull.Value;

}

works...shouldn't they be doing the same thing??

 

[Bruno Jouhier [MVP]]

You have to write it
object o = (1+2 == 3) ? (object)3 : DbNull.Value;

Compiler will bark if you have a conditional like :

T1 t1 = test ? t2 : t3 // t2 of type T2, t3 of type T3

and if neither T2 is assignable to T3, nor T3 assignable to T2 (even though
they may be both assignable to T1).

So, by casting t2 to object, you get T3 assignable to T2

Java works the same way.

Bruno.