Try:
namespace One
{
public class ClassOne
{
public int MyProperty { get; set; }
public ClassOne(int x, int y)
{
MyProperty = x + y;
}
}
}
namespace Two
{
public class CalssTwo
{
public void MyMethod()
{
One.ClassOne one = new One.ClassOne(23, 34);
Console.WriteLine(one.MyProperty);
}
}
}