static void Str_IsAndAs_1()
{
Griaffe g = new Griaffe();
FeedMammals(g);
SuperNova sn = new SuperNova();
TestForMammals(sn);
void FeedMammals(Animal a)
{
if (a is Mammal m)
{
m.Eat();
}
}
void TestForMammals(object o)
{
if (o is Mammal m)
{
Console.WriteLine(m.ToString());
}
else
{
Console.WriteLine($"{o.GetType().Name} is not a Mammal ");
}
}
}
static void Str_IsAndAs_3()
{
{
// Use the is operator to verify the type.
// before performing a cast.
Griaffe g = new Griaffe();
UseIsOperator(g);
// Use the as operator and test for null
// before referencing the variable.
UseAsOperator(g);
// Use the as operator to test
// an incompatible type.
SuperNova sn = new SuperNova();
UseAsOperator(sn);
// Use the as operator with a value type.
// Note the implicit conversion to int? in
// the method body.
int i = 5;
UseAsWithNullable(i);
double d = 9.78654;
UseAsWithNullable(d);
}
void UseIsOperator(Animal a)
{
if (a is Mammal)
{
Mammal m = (Mammal)a;
m.Eat();
}
}
void UsePatternMatchingIs(Animal a)
{
if (a is Mammal m)
{
m.Eat();
}
}
void UseAsOperator(object o)
{
Mammal m = o as Mammal;
if (m != null)
{
Console.WriteLine(m.ToString());
}
else
{
Console.WriteLine($"{o.GetType().Name} is not a Mammal");
}
}
void UseAsWithNullable(System.ValueType val)
{
int?j = val as int?;
if (j != null)
{
Console.WriteLine(j);
}
else
{
Console.WriteLine("Could not convert " + val.ToString());
}
}
}
