c++builder怎么查找电脑COM口

c++builder如何查找电脑COM口
请教下，我用MSCOMM控件编写了一个串口通信的软件，我想实现软件自动识别电脑COM口？请问下各位大侠如何实现？

[解决办法]
遍历打开串口号（如COM1-COM16） 如果打开成功说明这个串口号是存在的
[解决办法]
为啥不用现成的组件呢？
[解决办法]
从注册中表枚举就行了:
HKLM\HARDWARE\DEVICEMAP\SERIALCOMM
[解决办法]
摘录了一段,自己改

C/C++ code

TRegistry  *RegistryBoot = new   TRegistry(KEY_READ);  TStringList *NameList = new TStringList ;   //RegistryBoot   =   new   TRegistry;   ComboBox1->Items->Clear();   RegistryBoot->RootKey = HKEY_LOCAL_MACHINE;   RegistryBoot->OpenKey("HARDWARE\\DEVICEMAP\\SERIALCOMM",false);   RegistryBoot->GetValueNames(NameList);   //ShowMessage(NameList->Count);   for(int i = 0;i < NameList->Count ;i++ )   {  AnsiString Com = RegistryBoot->ReadString(NameList->Strings[i]);   //ShowMessage(Com);   ComboBox1->Items->Add(Com);   }   RegistryBoot->CloseKey() ;   delete RegistryBoot;   delete NameList;
[解决办法]
       //ComPort 參考:  http://topic.csdn.net/t/20050217/10/3786966.html
       HANDLE h=INVALID_HANDLE_VALUE;
       for(int i=1;i<33;i++)           //逐一對ComPort檢測
       {
               AnsiString ComName="Com"+String(i);
               h=::CreateFile(ComName.c_str(),GENERIC_READ | GENERIC_WRITE,0,0,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);
               if(h==INVALID_HANDLE_VALUE)         //若無法打開指定ComPort
               {
                       DWORD err=::GetLastError() ;    //讀取錯誤信息
                       if(err!=2)                      //若err=2,此COMPort未安裝
                       {
                               mmo1->Lines ->Add(ComName+" Error: "+AnsiString(err));
                              
                       }
               }
               else
               {
                       cbbPort ->Items ->Add(ComName);
                       cbPort2 ->Items ->Add(ComName);
               }
               CloseHandle(h);
       }
       //ComPort 參考:  http://topic.csdn.net/t/20050217/10/3786966.html
[解决办法]
這個我有自己用，不錯，被我改了一下
[解决办法]
   TStringList *tmp = new TStringList;   //自動取得COM Port的數量
  TRegistry *reg = new TRegistry;
  reg->RootKey = HKEY_LOCAL_MACHINE;

  if(reg->OpenKey("\\HARDWARE\\DEVICEMAP\\SERIALCOMM",false))
  {
 reg->GetValueNames(tmp);
  cbbCom->Clear();
    for(int i=0;i<tmp->Count;i++)
    {
      AnsiString asCOM = reg->ReadString(tmp->Strings[i]);
   cbbCom->Items->Add(asCOM);
 }
 reg->CloseKey();
  }
  delete reg;
  delete tmp;