ClassB inherits ClassA. How do I check if ClassA objA is of ClassB type and then convert objA to ClassB?

Question

Say that ClassB inherits ClassA, and that I have an object named objA that is of type ClassA. How do I check if objA is of ClassB type and then convert objA to ClassB?

Answer 1

You can do this:

var objB = objA as ClassB;
if (objB != null)
{
    // objA is of type ClassB, you can use it via objB
}

Or, if you're using C# 7:

if (objA is ClassB objB)
{
    // objA is of type ClassB, you can use it via objB
}