Exercise 3-9 (StaticFun, Increment static field)

Chapter_3     Exercise_3-8

StaticField     Exercise_3-10

---

---

Exercise 3-9     TCS, p. 86

Exercise 3-9. Turn the StaticFun code fragments into a working program.

Increment.cs     TCS, p. 70-71

public class Increment
{
public class StaticTest // inner class
{
public static int i = 47;
}

public class StaticFun // inner class
{
public static void Increment()
{ // access static field in a static context:
StaticTest.i++;
}
}

public static void Main()
{
StaticTest st1 = new StaticTest();
StaticTest st2 = new StaticTest();
// System.Console.WriteLine("st1.i = " + st1.i); // compile errors
// System.Console.WriteLine("st2.i = " + st2.i);
System.Console.WriteLine("StaticTest.i = " + StaticTest.i);
StaticFun sf = new StaticFun();
// sf.Increment(); // compile error
StaticFun.Increment();
System.Console.WriteLine("StaticTest.i = " + StaticTest.i);
// new StaticFun().Increment(); // compile error
StaticTest.i++; // access static field in a static context, Main()
System.Console.WriteLine("StaticTest.i = " + StaticTest.i);
// new StaticTest().i++; // compile error
}
}
/*
mcs Increment.cs
// 3 warnings: st1, st2, sf not used

mono Increment.exe
StaticTest.i = 47
StaticTest.i = 48
StaticTest.i = 49
*/

---

---

Chapter_3     Exercise_3-8

BACK_TO_TOP

StaticField     Exercise_3-10