Compiler Error CS0172
Visual Studio .NET 2003
Type of conditional expression can't be determined because 'type1' and 'type2' both implicitly convert to each other
In a conditional statement, you must be able to convert the types on either side of the : operator. Also, there cannot be mutual conversion routines; you only need one conversion.
The following sample generates CS0172:
// CS0172.cs
public class Square
{
public class Circle
{
public static implicit operator Circle(Square aa)
{
return null;
}
public static implicit operator Square(Circle aa)
// using explicit resolves this error
// public static explicit operator Square(Circle aa)
{
return null;
}
}
public static void Main()
{
Circle aa = new Circle();
Square ii = new Square();
object o = (1 == 1) ? aa : ii; // CS0172
// the following cast would resolve this error
// (1 == 1) ? aa : (Circle)ii;
}
}
