BCB6.0 自动识别USB串口设备

【实例截图】

【核心代码】

//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
#include "Initguid.h"
#include <Registry.hpp>
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"

TForm1 *Form1;

DEFINE_GUID(GUID_DEVINTERFACE_USB_DEVICE, 0xA5DCBF10,0x6530,0x11D2,0x90,0x1F,0x00,0xC0,0x4F,0xB9,0x51,0xED);
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
    SetUSBNotify(Application);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::SetUSBNotify(TObject *Sender)
{
    DEV_BROADCAST_DEVICEINTERFACE DevInt;
    //将指定内存块填充0
    memset(&DevInt,0,sizeof(DEV_BROADCAST_DEVICEINTERFACE));
    DevInt.dbcc_size        = sizeof(DEV_BROADCAST_DEVICEINTERFACE);
    DevInt.dbcc_devicetype  = DBT_DEVTYP_DEVICEINTERFACE;
    DevInt.dbcc_classguid   = GUID_DEVINTERFACE_USB_DEVICE;
    m_DevNotify             = RegisterDeviceNotification(this->Handle,&DevInt,DEVICE_NOTIFY_WINDOW_HANDLE);
    if(m_DevNotify == NULL)
    {
        ShowMessage("设备未注册成功");
    }
}
//---------------------------------------------------------------------------
int __fastcall TForm1::FindPort(LPARAM iMsgLParam)
{
    int portNo = 0;
    int NameLen = 0;
    wchar_t CurrentName[256];
    TStringList *myInfo = new TStringList();
    DEV_BROADCAST_HDR *lpDevHdr = (DEV_BROADCAST_HDR*)iMsgLParam;

    if(lpDevHdr->dbch_devicetype == DBT_DEVTYP_DEVICEINTERFACE)
    {
        DEV_BROADCAST_DEVICEINTERFACE *lpb = (DEV_BROADCAST_DEVICEINTERFACE *)iMsgLParam;
        myInfo->Delimiter = '#';
        NameLen = lpb->dbcc_size;
        memcpy(CurrentName,lpb->dbcc_name,NameLen);
        myInfo->DelimitedText = CurrentName;

        String keyPath = "SYSTEM\\CurrentControlSet\\Enum\\USB\\"   myInfo->Strings[1]
                    "\\"   myInfo->Strings[2] "\\Device Parameters";

        String portName = GetRegKeyValue(keyPath,"PortName");

        if(portName.SubString(1,3).UpperCase()=="COM")
        {
            portNo = atoi(portName.SubString(4,portName.Length()).c_str());
        }
    }

    myInfo->Clear();
    delete myInfo;
    return portNo;

}
//---------------------------------------------------------------------------
String __fastcall TForm1::GetRegKeyValue(String keyPath,String readStr)
{
    TRegistry *reg = NULL;
    String valueStr = "";
    try
    {
        try
        {
            reg = new TRegistry;
            reg->RootKey = HKEY_LOCAL_MACHINE;
            reg->OpenKey(keyPath,false);
            valueStr = reg->ReadString(readStr);
            reg->CloseKey();
        }
        catch(Exception &e)
        {
            //ignore errors
        }
    }
    __finally
    {
        if(reg)
        delete reg;
    }
    return  valueStr;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::WndProc(TMessage &Msg)
{
    if(Msg.Msg == WM_CLOSE)
    {
        if(IDNO == MessageBox(this->Handle,"确定退出软件吗？","提示",MB_YESNO))
        {
            return;
        }
    }
    if(Msg.Msg == WM_DEVICECHANGE)
    {
        switch(Msg.WParam)
        {
            case DBT_DEVICEARRIVAL:
            {
                int port = FindPort(Msg.LParam);
                if(port != 0)
                    ShowMessage("串口" AnsiString(port) "插入");

                break;
            }
            case DBT_DEVICEREMOVECOMPLETE:
            {
                int port = FindPort(Msg.LParam);
                if(port != 0)
                    ShowMessage("串口" AnsiString(port) "移除");

                break;
            }
            default:
                break;
        }
    }
    TForm::WndProc(Msg);
}