USB转串口线的COM口侦测问题

Question

我在程序开发过程中用到了USB转串口线，但是它虚拟成COM口后端口自动侦测就成了一个问题。在有的笔记本上它被虚拟成了COM17，如果我用程序循环从COM1到COM20，这也太慢了也太蠢了。请问哪位高手可以赐教，用WindowsAPI或者其他一些方式获取Windows的USB转串口所形成的虚拟COM口号！

Answer 1

你的计算机不可能有1－20个串口，你就读注册表，注册表中的串口一个一个的真测，不会太多的。下面是读注册表串口信息的代码 HKEY hKey;
LONG ret;
OSVERSIONINFO  osvi;
BOOL bOsVersionInfoEx;
char keyinfo[100],comm_name[40],ValueName[40];
int i;
DWORD sType,Reserved,cbData,cbValueName; hIcon=AfxGetApp()->LoadIcon(IDI_HARDWARE);
SetIcon(hIcon,false); ZeroMemory(&osvi, sizeof(OSVERSIONINFO));
    osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);

memset(keyinfo,0,100);
strcpy(keyinfo,"HARDWARE\\DEVICEMAP\\SERIALCOMM");
    i=0; sType=REG_SZ;Reserved=0;
bOsVersionInfoEx =GetVersionEx(&osvi);
    ret=RegOpenKeyEx(HKEY_LOCAL_MACHINE,keyinfo,0,KEY_ALL_ACCESS,&hKey);
if (ret==ERROR_SUCCESS){
// 10-25
   if (osvi.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS) 
   {
   for(i=1;i<=128;i++)
   {    
      sprintf(comm_name,"COM%d",i);
  if (CommPortIsUsed(comm_name)==1) m_comlist.AddString(comm_name);
   }
   }
       else if (osvi.dwPlatformId == VER_PLATFORM_WIN32_NT)
   {
    do 
  {
    cbData=40;cbValueName=40;
    memset(comm_name,0,40); 
    memset(ValueName,0,40);
    ret=RegEnumValue(hKey,i,ValueName,&cbValueName,NULL,&sType,(LPBYTE)comm_name,&cbData);
            if (ret==ERROR_SUCCESS)
{
               if (CommPortIsUsed(comm_name)==1) m_comlist.AddString(comm_name);
   i++;
}
  }while (ret==ERROR_SUCCESS);
   }
}

RegCloseKey(hKey);

Answer 2

//这是我写的用来读可用串口的函数，记得“uses Registry”,cobComName为TComboBox控件
//读取可用串口
function getComNames():TStringList;
var
  reg:TRegistry;
  strName:TStringList;
  i:integer;
begin
  strName:=TStringList.Create;
  reg:= TRegistry.Create;
  reg.RootKey:=HKEY_LOCAL_MACHINE;
  if reg.OpenKeyReadOnly('hardware\devicemap\serialcomm') then
  begin
    reg.GetValueNames(strName);
  end;
  Result:=TStringList.Create;
  for i:=0 to strName.Count-1 do
    Result.Add(reg.ReadString(strName.Strings[i]));
  reg.CloseKey;
  reg.Destroy;
end;
//添充到
procedure TFcomPara.FormCreate(Sender: TObject);
var Reg: TRegistry;
  strName:TStringList;
  i:integer;
begin
  strName:=getComNames();
  cobComName.Clear;
  for i:=0 to strName.Count-1 do
    cobComName.AddItem(strName[i],self);
  cobComName.ItemIndex:=0;
end;