C#

<code>
class TestClass {

   public event EventHandler TestEvent1;
   public event EventHandler TestEvent2;
   ...

   public TestClass() {}
}
</code> 

class MainForm : Form {

   TestClass testObj;

   public MainForm() {
      testObj.TestEvent1 += new EventHandler(testObj_TestEvent1);
      testObj.TestEvent2 += new EventHandler(testObj_TestEvent2);
   }

   void testObj_TestEvent1 (object sender, EventArgs e){}

   void testObj_TestEvent2 (object sender, EventArgs e){}
}

class SecondForm: Form {

   TestClass testObj;

   public SecondForm(TestClass obj) {
                  
      if(obj == null){
        throw new ArgumentNullException();
      }
  
      testObj = obj;
      testObj.TestEvent1 += new EventHandler(testObj_TestEvent1);
      testObj.TestEvent2 += new EventHandler(testObj_TestEvent2);
   }

   void testObj_TestEvent1 (object sender, EventArgs e){}

   void testObj_TestEvent2 (object sender, EventArgs e){}
}