chap2.lst

Csharp2完全参考手册源代码 详细的说明可以在书里看到 该书是08年刚出炉很新鲜

listing 1
/*  
   This is a simple C# program. 
 
   Call this program Example.cs. 
*/ 
 
using System; 
 
class Example { 
  // A C# program begins with a call to Main(). 
  public static void Main() { 
    Console.WriteLine("A simple C# program."); 
  } 
}

listing 2
// This version does not include the using System statement. 
 
class Example { 
 
  // A C# program begins with a call to Main(). 
  public static void Main() { 
 
    // Here, Console.WriteLine is fully qualified. 
    System.Console.WriteLine("A simple C# program."); 
  } 
}

listing 3
// This program demonstrates variables.  
 
using System; 
 
class Example2 {   
  public static void Main() {   
    int x; // this declares a variable  
    int y; // this declares another variable  
  
    x = 100; // this assigns 100 to x 
  
    Console.WriteLine("x contains " + x);   
  
    y = x / 2;  
  
    Console.Write("y contains x / 2: ");  
    Console.WriteLine(y);  
  }   
}

listing 4
/*  
   This program illustrates the differences 
   between int and double. 
*/  
 
using System; 
 
class Example3 {  
  public static void Main() {  
    int ivar;     // this declares an int variable 
    double dvar;  // this declares a floating-point variable 
 
    ivar = 100;   // assign ivar the value 100 
    
    dvar = 100.0; // assign dvar the value 100.0 
 
    Console.WriteLine("Original value of ivar: " + ivar); 
    Console.WriteLine("Original value of dvar: " + dvar); 
 
    Console.WriteLine(); // print a blank line 
 
    // now, divide both by 3 
    ivar = ivar / 3;  
    dvar = dvar / 3.0; 
 
    Console.WriteLine("ivar after division: " + ivar); 
    Console.WriteLine("dvar after division: " + dvar); 
  }  
}

listing 5
// Compute the area of a circle. 
  
using System;  
   
class Circle {   
  public static void Main() {   
    double radius; 
    double area; 
 
    radius = 10.0; 
    area = radius * radius * 3.1416; 
 
    Console.WriteLine("Area is " + area); 
  }   
}

listing 6
// Demonstrate the if.  
 
using System; 
 
class IfDemo {  
  public static void Main() {  
    int a, b, c;  
  
    a = 2;  
    b = 3;  
  
    if(a < b) Console.WriteLine("a is less than b"); 
 
    // this won't display anything  
    if(a == b) Console.WriteLine("you won't see this");  
 
    Console.WriteLine(); 
 
    c = a - b; // c contains -1 
 
    Console.WriteLine("c contains -1"); 
    if(c >= 0) Console.WriteLine("c is non-negative"); 
    if(c < 0) Console.WriteLine("c is negative"); 
 
    Console.WriteLine(); 
 
    c = b - a; // c now contains 1 
    Console.WriteLine("c contains 1"); 
    if(c >= 0) Console.WriteLine("c is non-negative"); 
    if(c < 0) Console.WriteLine("c is negative"); 
  }  
}

listing 7
// Demonstrate the for loop. 
 
using System; 
 
class ForDemo { 
  public static void Main() { 
    int count; 
 
    for(count = 0; count < 5; count = count+1) 
      Console.WriteLine("This is count: " + count); 
 
    Console.WriteLine("Done!"); 
  } 
}

listing 8
// Demonstrate a block of code. 
 
using System; 
 
class BlockDemo { 
  public static void Main() { 
    int i, j, d; 
 
    i = 5; 
    j = 10; 
 
    // the target of this if is a block 
    if(i != 0) { 
      Console.WriteLine("i does not equal zero"); 
      d = j / i; 
      Console.WriteLine("j / i is " + d); 
    } 
  } 
}

listing 9
// Compute the sum and product of the numbers from 1 to 10. 
  
using System;  
   
class ProdSum {   
  public static void Main() {   
    int prod; 
    int sum; 
    int i; 
 
    sum = 0; 
    prod = 1; 
 
    for(i=1; i <= 10; i++) { 
      sum = sum + i; 
      prod = prod * i;       
    } 
    Console.WriteLine("Sum is " + sum); 
    Console.WriteLine("Product is " + prod); 
 
  }   
}

listing 10
// Demonstrate an @ identifier. 
  
using System;  
   
class IdTest {   
  public static void Main() {   
    int @if; // use if as an identifier 
 
    for(@if = 0; @if < 10; @if++) 
      Console.WriteLine("@if is " + @if); 
  }   
}