How to avoid boxing and ugly switch statements

Say we have the following :

object[] objs = new object[3]{ "the ultimate question", 42L, 1}; 

and we want to do something to the individual objects in the array like :

foreach (object o in objs)
{
   dosomething(o);
}

Now dosomething will only take object parameters so there is boxing going on, but we require to be able to do something based on the type of the object, so we would do something like :

public void dosomething(object obj)
{ 
   // one way
   if(obj.GetType() == typeof(string))
   {
      // string specific something
   }
   // another way
   if(obj is long)
   {
      // long specific something
   }
   
}

Well it's ugly and non performant, is there a better way possible using generics etc.?

Tags: C#