1. 首先引用winsock单元

 function   PingHost(HostIP:   String): Boolean;
type
    PIPOptionInformation=^TIPOptionInformation;
    TIPOptionInformation=packed   record
     TTL:   Byte;
     TOS:   Byte;
     Flags:   Byte;
     OptionsSize:   Byte;
     OptionsData:   PChar;
end;

 PIcmpEchoReply=^TIcmpEchoReply;
 TIcmpEchoReply=packed   record
 Address : DWORD;
 Status : DWORD;
 RTT:   DWORD;
 DataSize:   Word;
 Reserved:   Word;
 Data:   Pointer;
 Options:   TIPOptionInformation;
 end;
 TIcmpCreateFile   =   function:   THandle;   stdcall;
 TIcmpCloseHandle   =   function(IcmpHandle:   THandle):   Boolean;   stdcall;
 TIcmpSendEcho   =   function(IcmpHandle:THandle;
 DestinationAddress:   DWORD;
 RequestData:   Pointer;
 RequestSize:   Word;
 RequestOptions:   PIPOptionInformation;
 ReplyBuffer:   Pointer;
 ReplySize:   DWord;
 Timeout:   DWord
 ):   DWord;   stdcall;
var   
      hICMP : THandle;
      hICMPdll : THandle;
      IcmpCreateFile : TIcmpCreateFile;
      IcmpCloseHandle : TIcmpCloseHandle;
      IcmpSendEcho : TIcmpSendEcho;
      pIPE : PIcmpEchoReply;//   ICMP   Echo   reply   buffer
      FIPAddress : DWORD;
      FSize :   DWORD;
      FTimeOut :  DWORD;
      BufferSize : DWORD;
      pReqData,pRevData:PChar;   
      MyString:string;   
begin   
      Result:=False;
      hICMPdll:=LoadLibrary(\'icmp.dll\');
      if   hICMPdll=0 then exit;
      @ICMPCreateFile:=GetProcAddress(hICMPdll,   \'IcmpCreateFile\');
      @IcmpCloseHandle:=GetProcAddress(hICMPdll,\'IcmpCloseHandle\');
      @IcmpSendEcho:=GetProcAddress(hICMPdll,   \'IcmpSendEcho\');

      hICMP:=IcmpCreateFile;
    
      if(hICMP=INVALID_HANDLE_VALUE)   then   exit;
    
      FIPAddress:=  inet_addr(PChar(HostIP));
      MyString:=  \'Hello\'; //send   data   buffer
      pReqData:=  PChar(MyString);
    
      FSize:=40;//receive   data   buffer
      BufferSize:=SizeOf(TICMPEchoReply)+FSize;
      GetMem(pIPE,BufferSize);   
      FillChar(pIPE^,SizeOf(pIPE^),0);
      GetMem(pRevData,FSize);   
      pIPE^.Data:=pRevData;
      FTimeOut:=50;//超时时间,毫秒
      try
          Result:=IcmpSendEcho(hICMP,FIPAddress,pReqData,
          Length(MyString),nil,pIPE,BufferSize,FTimeOut)>0;
      finally   
          IcmpCloseHandle(hICMP);
          FreeLibrary(hICMPdll);   
          FreeMem(pRevData);   
          FreeMem(pIPE);   
      end;   
end;

true 能Ping通 否则无此主机。

2. 快速设置本地ip

if not pinghost(ip4) then
        begin
          winstr:=\'netsh  interface ip set address 本地连接 static  192.168.1.9  255.255. 255.0  192.168.1.1  1\';
          WinExec(PChar(winstr),SW_HIDE);
        end;