c#调用c++方法介绍,window api

例子1如下:

//声明部分

[dllimport("um_web_client.dll")]
  private static extern int checkusername(string username);

//

public static int authusername(string username)
  {
   if(!isconnection())
   {
    startwebclient(udbclientip,udbclientport,udbclienttimeout);
   }
   return checkusername(username);
  }

但是如果c++方法中用了指针或者结构体等则引用就要注意,相应就要用到引用数组或者指针,例子2:

声明部分

[structlayout(layoutkind.sequential, charset=charset.ansi )]
  public class tagplayerinfoout
  {
   public int id;
   public string playername;
   public int country;
   public int officerrace;
   public int level;
   public int militaryrank;
   public int money;
   public int resourcecount;
   public int citycount;
   public int generalcount;
   public int credit;
  }

  [ structlayout( layoutkind.sequential )]
  public struct tagplayerinfooutex
  {
   public int id;
   public intptr playername;
   public int country;
   public int officerrace;
   public int level;
   public int militaryrank;
   public int money;
   public int resourcecount;
   public int citycount;
   public int generalcount;
   public int credit;
  }

 

[dllimport("um_web_client.dll")]
  public static extern int getplayerlistcs(int maxrows, out int rows,  out intptr playerlist);

  [dllimport("um_web_client.dll")]
  public static extern int getplayerlistcs(int maxrows, out int rows, tagplayerinfooutex** playerlist);

方法

public static datatable usingmarshal()
  {
   if(!isconnection())
   {
    startwebclient(udbclientip,udbclientport,udbclienttimeout);
   }
   datatable dt = new datatable();

   dt.columns.add("id");
   dt.columns.add("playername");
   dt.columns.add("country");
   dt.columns.add("officerrace");
   dt.columns.add("level");
   dt.columns.add("militaryrank");
   dt.columns.add("money");
   dt.columns.add("resourcecount");
   dt.columns.add("citycount");
   dt.columns.add("generalcount");
   dt.columns.add("credit");

   int size = 0;
   intptr outarray;
   getplayerlistcs(20, out size, out outarray);
   tagplayerinfoout[] manarray = new tagplayerinfoout[size];
   intptr current = outarray;
   //console.writeline("记录数{0}",size);

   for( int i = 0; i < size; i++ )
   {
    manarray[ i ] = new tagplayerinfoout();
    marshal.ptrtostructure(current, manarray[i]);
    marshal.destroystructure(current, typeof(tagplayerinfoout) );
    current = (intptr)((long)current + marshal.sizeof(manarray[i]));

    dt.rows.add(new object[] {manarray[i].id,manarray[i].playername,manarray[i].country,manarray[i].officerrace,manarray[i].level,manarray[i].militaryrank,manarray[i].money,manarray[i].resourcecount,manarray[i].citycount,manarray[i].generalcount,manarray[i].credit});

    dt.acceptchanges();
   //console.writeline( "element {0}: {1} {2}", i, manarray[i].id, manarray[i].playername);
  }
   marshal.freecotaskmem(outarray);
   return dt;
  }

  public static unsafe datatable usingunsafe()
  {
   int size;
   if(!isconnection())
   {
    startwebclient(udbclientip,udbclientport,udbclienttimeout);
   }
   datatable dt = new datatable();

   dt.columns.add("id");
   dt.columns.add("playername");
   dt.columns.add("country");
   dt.columns.add("officerrace");
   dt.columns.add("level");
   dt.columns.add("militaryrank");
   dt.columns.add("money");
   dt.columns.add("resourcecount");
   dt.columns.add("citycount");
   dt.columns.add("generalcount");
   dt.columns.add("credit");
   tagplayerinfooutex* presult;
   getplayerlistcs(20,  out size, &presult );
   tagplayerinfooutex* pcurrent = presult;
   //console.writeline("记录数{0}",size);

   for( int i = 0; i < size; i++, pcurrent++ )
   {
    //console.writeline( "element {0}: {1} {2}", i, pcurrent->id ,marshal.ptrtostringansi(pcurrent->playername));
    //marshal.freecotaskmem(pcurrent->playername );
    dt.rows.add(new object[] {pcurrent->id,pcurrent->playername,pcurrent->country,pcurrent->officerrace,pcurrent->level,pcurrent->militaryrank,pcurrent->money,pcurrent->resourcecount,pcurrent->citycount,pcurrent->generalcount,pcurrent->credit});

    dt.acceptchanges();
   }
   marshal.freecotaskmem((intptr)presult );
   return dt;
  }