C#

public static explicit operator MyCar(object o)
{
if(o is string)
 return new MyCar((string)o);
if(0 is int)
 return new MyCar((int)o);
}

private static MyCar GetMyCar(object car)   // car is a boxed string or int  
{
    if (car is string)
    {
        return (MyCar)((string)car);
    }
    else if (car is int)
    {
        return (MyCar)((int)car);
    }
    else if (car is MyCar)
    {
        return (MyCar)car;
    }
    throw new ArgumentException("Object must be MyCar, string or int.");
}

object o= value;        // value is of type int, but this function does not know it
MyCar car = (MyCar)o;   // Fails

Eric Lippert wrote:

All that the compiler knows is that [your object] is of type object. It could be anything. Suppose it is a boxed int – then the compiler should generate an unboxing instruction. Suppose it is a boxed short. Then the compiler should unbox the short and then generate the custom sequence of instructions that convert a short to an int. Suppose it is a boxed double – same thing, but different instructions. And so on, for all the built-in conversions that go to integer.

public static MethodInfo GetMethod(Type toSearch, string methodName, Type inputType, BindingFlags bindingFlags)
{
    return Array.Find(toSearch.GetMethods(bindingFlags),
        delegate(System.Reflection.MethodInfo inf) {
            return ((inf.Name == methodName) && (inf.ReturnType == toSearch) && inf.GetParameters().Length == 1 && inf.GetParameters()[0].ParameterType == inputType); });
}

public static T DynamicCast<T>(object o)
{
    Type objectType = o.GetType();
    Type returnType = typeof(T);

    MethodInfo meth = GetMethod(returnType, "op_Implicit", objectType, BindingFlags.Static | BindingFlags.Public);
    if (meth == null)
    {
        meth = GetMethod(returnType, "op_Explicit", objectType, BindingFlags.Static | BindingFlags.Public);
    }
    if (meth == null)
        throw new InvalidCastException("Invalid Cast.");
    return (T)meth.Invoke(null, new object[] { o });
}

System.ServiceProcess.ServiceController serviceController = new System.ServiceProcess.ServiceController();

serviceController.ServiceName = "MyService";

serviceController.Start();

serviceController.WaitForStatus(System.ServiceProcess.ServiceControllerStatus.Running);

serviceController.Stop();

serviceController.WaitForStatus(System.ServiceProcess.ServiceControllerStatus.Stopped);