Question

求解一段简单的C#代码

下面是一段C#代码，我不是太懂，大概的意思是用类似于[DllImport("kernel32.dll")]这样的东西来调用打印机来打印文件，但是我还是看不太懂每一行或者每一个方法的意思，有没有哪位C#大神帮我注释一下或者解释一下这段代码每一段的意思啊，每一个方法分别是干什么用的，谢谢，代码如下：
using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;
namespace Barcode_Print
{
class LPTControl
{
[StructLayout(LayoutKind.Sequential)]
private struct OVERLAPPED
{
int Internal;
int InternalHigh;
int Offset;
int OffSetHigh;
int hEvent;
}

[DllImport("kernel32.dll")]
private static extern int CreateFile(
string lpFileName,
uint dwDesiredAccess,
int dwShareMode,
int lpSecurityAttributes,
int dwCreationDisposition,
int dwFlagsAndAttributes,
int hTemplateFile
);

[DllImport("kernel32.dll")]
private static extern bool WriteFile(
int hFile,
byte[] lpBuffer,
int nNumberOfBytesToWrite,
out int lpNumberOfBytesWritten,
out OVERLAPPED lpOverlapped
);

[DllImport("kernel32.dll")]
private static extern bool CloseHandle(
int hObject
);

private int iHandle;
public bool Open()
{
iHandle = CreateFile("lpt1", 0x40000000, 0, 0, 3, 0, 0);
if (iHandle != -1)
{
return true;
}
else
{

Answer 1

debug下，就知道实际情况了：
执行顺序如下：
public static int Y=A.X+1; //此时B.Y = 0;
public static int X; //此时A.X = 0;
static A(){ X=B.Y+1; } //此时A.X = 1;
又回到public static int Y = A.X + 1; //此时B.Y = 2;
static B(){}

静态类执行顺序
静态变量的初始化（并附默认值）
静态构造函数

要多实际操作，才能帮助我们理解程序。

请采纳答案，支持我一下。

Answer 2

using   System;   
using   System.Collections.Generic;   
using   System.Text;   
using   System.Runtime.InteropServices;       //这个引用不能缺！

namespace   Barcode_Print   //命名空间为 Barcode_Print
 {   
         // LPTControl 类
          class   LPTControl   
          {   
                  //[StructLayout(……)]用来约束OVERLAPPED在内存中存放方式 
                  [StructLayout(LayoutKind.Sequential)]   
                    
                  private   struct   OVERLAPPED   
                  {   
                          int   Internal;   
                          int   InternalHigh;   
                          int   Offset;   
                          int   OffSetHigh;   
                          int   hEvent;   
                  }   
                  //[DllImport("kernel32.dll")]用来引入动态链接库 kernel32.dll  
                  [DllImport("kernel32.dll")] 

                  // CreateFile 是动态链接库 kernel32.dll 中的函数 
                  // 在C#中，动态链接库中函数必须用 static extern
                  private   static   extern   int   CreateFile(   
                  string   lpFileName,   
                  uint   dwDesiredAccess,   
                  int   dwShareMode,   
                  int   lpSecurityAttributes,   
                  int   dwCreationDisposition,   
                  int   dwFlagsAndAttributes,   
                  int   hTemplateFile   
                  );   

                  [DllImport("kernel32.dll")]   
                  // WriteFile 是动态链接库 kernel32.dll 中的函数 
                  private   static   extern   bool   WriteFile(   
                  int   hFile,   
                  byte[]   lpBuffer,   
                  int   nNumberOfBytesToWrite,   
                  out   int   lpNumberOfBytesWritten,   
                  out   OVERLAPPED   lpOverlapped   
                  );   

                  [DllImport("kernel32.dll")]   
                  // CloseHandle 是动态链接库 kernel32.dll 中的函数   
                  private   static   extern   bool   CloseHandle(   
                  int   hObject   
                  );   
                  
                  // 私有变量  
                  private   int   iHandle;   
                  // 类方法 Open 
                  public   bool   Open()   
                  {   
                          // 调用动态链接库中的函数CreateFile
                          iHandle   =   CreateFile("lpt1",   0x40000000,   0,   0,   3,   0,   0);   
                          if   (iHandle   !=   -1)   
                          {   
                                  return   true;   
                          }   
                          else   
                          {
                          ……
                          }
                   }
                   
               }
}

追问

由于字数限制，后面还有一小部分代码，追问这里还是写不下，这里是链接，里面有完整版的，把后面的也请帮我注释一下呗，谢谢了。

http://zhidao.baidu.com/question/1702782659547597300.html?quesup2&oldq=1