C# 0 The Complete Reference

i

 inside the 

for

:

// Declare loop control variable inside the for.

using System;

class ForVar {

  static void Main() {

    int sum = 0;

    int fact = 1;

    // Compute the factorial of the numbers 1 through 5.

    for(int i = 1; i <= 5; i++) {

      sum += i;  // i is known throughout the loop.

      fact *= i;

    }

    // But, i is not known here.

    Console.WriteLine("Sum is " + sum);

    Console.WriteLine("Factorial is " + fact);

  }

}

When you declare a variable inside a 

for

 loop, there is one important point to remember: 

The scope of that variable ends when the 

for

 statement does. (That is, the scope of the variable 

is limited to the 

for

 loop.) Outside the 

for

 loop, the variable will cease to exist. Thus, in the 

preceding example,