我正在尝试枚举COM端口的“友好名称”。随着USB串行设备在运行时连接和断开，端口可能会动态变化。
基于this question中描述的可能方法，我试图使用SetupDiGetClassDevs方法。
我找到了this example code，但它是为旧版本的setupapi单元编写的（homepages.borland.com的原始链接当然不起作用）。
我尝试使用当前JVCL（JVCL340CompleteJCL221-Build3845）中的setupapi单元，但它似乎与Delphi 7不兼容。我收到编译器错误：
if SetupDiGetDeviceRegistryProperty(DevInfoHandle,DeviceInfoData,
RegProperty,
@PropertyRegDataType,
@S1[1],RequiredSize,@RequiredSize) then begin
在对函数 SetupDiGetDeviceRegistryProperty 的调用中， 我在参数 @PropertyRegDataType 和 @RequiredSize 上得到错误“实际和形式参数的类型必须相同”。
Delphi3000站点说该代码是在2004年编写的，适用于Delphi 7，所以我不确定为什么它现在不适用于Delphi 7，除非setupapi已经改变。是否有人熟悉setupapi可能导致这些问题的更改？
我正在测试一个简单的控制台程序。用法声明是“窗口， sysutils的， 类， SETUPAPI， 注册表中;“
主要计划是：
begin
ComPortStringList := SetupEnumAvailableComPorts;
for Index := 0 to ComPortStringList.Count - 1 do
writeln(ComPortStringList[Index]);
end;
end.
答案 0 :(得分：9)
以下过程对我来说正常（在Windows 8.1中）。在KEY_READ。
TRegistry.Constructor非常重要
procedure EnumComPorts(const Ports: TStringList);
var
nInd: Integer;
begin { EnumComPorts }
with TRegistry.Create(KEY_READ) do
try
RootKey := HKEY_LOCAL_MACHINE;
if OpenKey('hardware\devicemap\serialcomm', False) then
try
Ports.BeginUpdate();
try
GetValueNames(Ports);
for nInd := Ports.Count - 1 downto 0 do
Ports.Strings[nInd] := ReadString(Ports.Strings[nInd]);
Ports.Sort()
finally
Ports.EndUpdate()
end { try-finally }
finally
CloseKey()
end { try-finally }
else
Ports.Clear()
finally
Free()
end { try-finally }
end { EnumComPorts };
答案 1 :(得分：5)
我能够通过asking the question a different way with different tags获得更具体的建议。
事实证明，delphi3000.com示例代码中存在错误，并且可能是JVCL代码中的错误。修复示例代码错误后，我让它工作。我没有解决潜在的JVCL错误。
以下是用于枚举com端口名称的工作代码（作为简单的控制台应用程序）：
{$APPTYPE CONSOLE}
program EnumComPortsTest;
uses
windows,
sysutils,
classes,
setupAPI,
Registry;
{$R *.RES}
var
ComPortStringList : TStringList;
(*
The function below returns a list of available COM-ports
(not open by this or an other process), with friendly names. The list is formatted as follows:
COM1: = Communications Port (COM1)
COM5: = NI Serial Port (Com5)
COM6: = NI Serial Port (Com6)
COM7: = USB Serial Port (COM7)
COM8: = Bluetooth Communications Port (COM8)
COM9: = Bluetooth Communications Port (COM9)
This code originally posted at http://www.delphi3000.com/articles/article_4001.asp?SK=
errors have been fixed so it will work with Delphi 7 and SetupAPI from JVCL
*)
function SetupEnumAvailableComPorts:TstringList;
// Enumerates all serial communications ports that are available and ready to
// be used.
// For the setupapi unit see
// http://homepages.borland.com/jedi/cms/modules/apilib/visit.php?cid=4&lid=3
var
RequiredSize: Cardinal;
GUIDSize: DWORD;
Guid: TGUID;
DevInfoHandle: HDEVINFO;
DeviceInfoData: TSPDevInfoData;
MemberIndex: Cardinal;
PropertyRegDataType: DWord;
RegProperty: Cardinal;
RegTyp: Cardinal;
Key: Hkey;
Info: TRegKeyInfo;
S1,S2: string;
hc: THandle;
begin
Result:=Nil;
//If we cannot access the setupapi.dll then we return a nil pointer.
if not LoadsetupAPI then exit;
try
// get 'Ports' class guid from name
GUIDSize := 1; // missing from original code - need to tell function that the Guid structure contains a single GUID
if SetupDiClassGuidsFromName('Ports',@Guid,GUIDSize,RequiredSize) then begin
//get object handle of 'Ports' class to interate all devices
DevInfoHandle:=SetupDiGetClassDevs(@Guid,Nil,0,DIGCF_PRESENT);
if Cardinal(DevInfoHandle)<>Invalid_Handle_Value then begin
try
MemberIndex:=0;
result:=TStringList.Create;
//iterate device list
repeat
FillChar(DeviceInfoData,SizeOf(DeviceInfoData),0);
DeviceInfoData.cbSize:=SizeOf(DeviceInfoData);
//get device info that corresponds to the next memberindex
if Not SetupDiEnumDeviceInfo(DevInfoHandle,MemberIndex,DeviceInfoData) then
break;
//query friendly device name LIKE 'BlueTooth Communication Port (COM8)' etc
RegProperty:=SPDRP_FriendlyName;{SPDRP_Driver, SPDRP_SERVICE, SPDRP_ENUMERATOR_NAME,SPDRP_PHYSICAL_DEVICE_OBJECT_NAME,SPDRP_FRIENDLYNAME,}
SetupDiGetDeviceRegistryProperty(DevInfoHandle,
DeviceInfoData,
RegProperty,
PropertyRegDataType,
NIL,0,RequiredSize);
SetLength(S1,RequiredSize);
if SetupDiGetDeviceRegistryProperty(DevInfoHandle,DeviceInfoData,
RegProperty,
PropertyRegDataType,
@S1[1],RequiredSize,RequiredSize) then begin
KEY:=SetupDiOpenDevRegKey(DevInfoHandle,DeviceInfoData,DICS_FLAG_GLOBAL,0,DIREG_DEV,KEY_READ);
if key<>INValid_Handle_Value then begin
FillChar(Info, SizeOf(Info), 0);
//query the real port name from the registry value 'PortName'
if RegQueryInfoKey(Key, nil, nil, nil, @Info.NumSubKeys,@Info.MaxSubKeyLen, nil, @Info.NumValues, @Info.MaxValueLen,
@Info.MaxDataLen, nil, @Info.FileTime) = ERROR_SUCCESS then begin
RequiredSize:= Info.MaxValueLen + 1;
SetLength(S2,RequiredSize);
if RegQueryValueEx(KEY,'PortName',Nil,@Regtyp,@s2[1],@RequiredSize)=Error_Success then begin
If (Pos('COM',S2)=1) then begin
//Test if the device can be used
hc:=CreateFile(pchar('\\.\'+S2+#0),
GENERIC_READ or GENERIC_WRITE,
0,
nil,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
0);
if hc<> INVALID_HANDLE_VALUE then begin
Result.Add(Strpas(PChar(S2))+': = '+StrPas(PChar(S1)));
CloseHandle(hc);
end;
end;
end;
end;
RegCloseKey(key);
end;
end;
Inc(MemberIndex);
until False;
//If we did not found any free com. port we return a NIL pointer.
if Result.Count=0 then begin
Result.Free;
Result:=NIL;
end
finally
SetupDiDestroyDeviceInfoList(DevInfoHandle);
end;
end;
end;
finally
UnloadSetupApi;
end;
end;
var
index : integer;
begin
ComPortStringList := SetupEnumAvailableComPorts;
if (ComPortStringList <> nil) and (ComPortStringList.Count > 0) then
for Index := 0 to ComPortStringList.Count - 1 do
writeln(ComPortStringList[Index]);
end.
答案 2 :(得分：2)
你打开了“打字@运营商”吗？项目选项，“语法选项”下的“编译器”选项卡。如果启用该选项，很多第三方代码都会中断。
答案 3 :(得分：2)
为了便于操作，您可以考虑简单地使用注册表，其中列出了这些名称，例如：
ErrCode := RegOpenKeyEx(
HKEY_LOCAL_MACHINE,
'HARDWARE\DEVICEMAP\SERIALCOMM',
0,
KEY_READ,
KeyHandle);
（我忽略了挥手的东西）。
您可能还会考虑使用WMI - 请参阅Magenta Systems的this example - 您现在可以获得与硬件相关的所有内容。
答案 4 :(得分：2)
类似PDWord的某些参数被var DWord中的SetupApi.pas取代。您只需要在代码中删除这些参数中的“@”，如下所示：
if SetupDiGetDeviceRegistryProperty(DevInfoHandle,DeviceInfoData,
RegProperty,
PropertyRegDataType,
@S1[1],RequiredSize,RequiredSize) then begin
答案 5 :(得分：0)
我改编了以下来自 RRUZ answer 的代码用于串行端口类。在 Win10 20H2 下工作正常。
{$APPTYPE CONSOLE}
uses
SysUtils,
ActiveX,
ComObj,
Variants;
procedure GetWin32_SerialPortInfo;
const
WbemUser ='';
WbemPassword ='';
WbemComputer ='localhost';
wbemFlagForwardOnly = $00000020;
var
FSWbemLocator : OLEVariant;
FWMIService : OLEVariant;
FWbemObjectSet: OLEVariant;
FWbemObject : OLEVariant;
oEnum : IEnumvariant;
iValue : LongWord;
begin;
FSWbemLocator := CreateOleObject('WbemScripting.SWbemLocator');
FWMIService := FSWbemLocator.ConnectServer(WbemComputer, 'root\CIMV2', WbemUser, WbemPassword);
FWbemObjectSet:= FWMIService.ExecQuery('SELECT * FROM Win32_SerialPort','WQL',wbemFlagForwardOnly);
oEnum := IUnknown(FWbemObjectSet._NewEnum) as IEnumVariant;
while oEnum.Next(1, FWbemObject, iValue) = 0 do
begin
// for other fields: https://docs.microsoft.com/en-us/windows/win32/cimwin32prov/win32-serialport
Writeln(Format('DeviceID %s',[String(FWbemObject.DeviceID)]));// String
Writeln(Format('Name %s',[String(FWbemObject.Name)]));// String
Writeln(Format('Description %s',[String(FWbemObject.Description)]));// String
FWbemObject:=Unassigned;
end;
end;
begin
try
CoInitialize(nil);
try
GetWin32_SerialPortInfo;
finally
CoUninitialize;
end;
except
on E:EOleException do
Writeln(Format('EOleException %s %x', [E.Message,E.ErrorCode]));
on E:Exception do
Writeln(E.Classname, ':', E.Message);
end;
Writeln('Press Enter to exit');
Readln;
end.
输出：
DeviceID COM7
Name Silicon Labs CP210x USB to UART Bridge (COM7)
Description Silicon Labs CP210x USB to UART Bridge
Press Enter to exit