获得系统RS232串口个数的API

[oken2]

获得系统RS232串口个数的API？
我现在VB中调用。这个API是什么？怎么在VB中调用

[现在还是人类]

以下方法同样能找出串口设备，不过需要自己加一下识别条件

//********************************************************************************
//**   函 数 名 ：	GetDeviceState
//**   输    入 ：	DeviceName				-  设备名称
//**   返    回 ：	BOOL					-  返回设备启用/禁用状态
//**   功能描述 ：	取得设备的启用或禁用状态
//********************************************************************************
long _stdcall GetDeviceState(char * DeviceName)
{
	//------------------------------------------------
	//              过程内局部变量定义
	//------------------------------------------------
	HDEVINFO				hDevInfo;
	SP_DEVINFO_DATA			DeviceInfoData;
	DWORD					i;
	VBString				sDeviceDescription;
	VBString				sDeviceName;
	BOOL					rd;
	DWORD					dwRegDataType;
	DWORD					dwBufferSize;
	BYTE					*bDevInfo;
	long					retdata	= 0;
	DWORD					Status;
	DWORD					Problem;
	//初始化基本参数
	sDeviceName = DeviceName;
	sDeviceName.set_UCase();
	//------------------------------------------------
	//先通过枚举所有设备找出指定设备名称的相关GUID信息
	//------------------------------------------------
	//程序开始设下错误陷阱防止意外崩溃
	hDevInfo = SetupDiGetClassDevs(NULL,NULL,NULL,DIGCF_PRESENT | DIGCF_ALLCLASSES);
	if(hDevInfo == INVALID_HANDLE_VALUE){
		return FALSE;
	}
	DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA);
	i = 0;
	//开始循环枚举设备信息
	while(SetupDiEnumDeviceInfo(hDevInfo, i, &DeviceInfoData)!=FALSE){
		//------ 取得设备名称 ------
		rd = SetupDiGetDeviceRegistryProperty(hDevInfo, 
											  &DeviceInfoData, 
											  SPDRP_DEVICEDESC, 
											  &dwRegDataType, 
											  NULL, 
											  NULL, 
											  &dwBufferSize);
		if(rd!=TRUE){
			bDevInfo = (BYTE *)GlobalAlloc(GMEM_ZEROINIT, dwBufferSize * 2);
			rd = SetupDiGetDeviceRegistryProperty(hDevInfo, 
												  &DeviceInfoData, 
												  SPDRP_DEVICEDESC, 
												  &dwRegDataType, 
												  bDevInfo, 
												  dwBufferSize, 
												  NULL);
			sDeviceDescription.set_Bytes(bDevInfo);
			sDeviceDescription.set_UCase();
			GlobalFree((HGLOBAL)bDevInfo);
			if(sDeviceDescription == *sDeviceName){
				if(CM_Get_DevNode_Status(&Status,&Problem,DeviceInfoData.DevInst,0)==CR_SUCCESS){
					if((Status & DN_HAS_PROBLEM) && (CM_PROB_DISABLED == Problem)){
						retdata=0;
					}else{
						retdata=1;
					}
				}
				break;
			}
		}
		i++;
	}
	SetupDiDestroyDeviceInfoList(hDevInfo);
	return retdata;
}

[jhone99]

[Quote=引用 6 楼 supermanking 的回复:]
VB code

Dim POSTObj As Object
Dim COMPost As Object
Combo1.Clear
Set POSTObj = WMIObj.InstancesOf("Win32_SerialPort")
For Each COMPost In POSTObj
'以下判断你的USB驱动名称进行识别
……
[/Quote]

SupermanKing 我加了
Dim WMIObj As Object
Set WMIObj = CreateObject("winmgmts://./root/cimv2")
才好用，你是不是贴漏了？

完整

Private Sub Command1_Click()
   Dim WMIObj As Object
   Set WMIObj = CreateObject("winmgmts://./root/cimv2")
   
   Dim POSTObj As Object
   Dim COMPost As Object
   
   Combo1.Clear
   Set POSTObj = WMIObj.InstancesOf("Win32_SerialPort")
   
   For Each COMPost In POSTObj
      '以下判断你的USB驱动名称进行识别
      Combo1.AddItem COMPost.Description & "(" & COMPost.DeviceID & ")"
      Combo1.ItemData(Combo1.ListCount - 1) = Int(Right(COMPost.DeviceID, Len(COMPost.DeviceID) - 3))
   Next
   
   Combo1.ListIndex = 0

End Sub

[现在还是人类]

呵呵，代码是从以前的程序截出来的，真的漏了

   Dim WMIObj As Object
   Set WMIObj = CreateObject("winmgmts://./root/cimv2")
   '对象信息 ================================================
   Dim POSTObj As Object
   Dim COMPost As Object
   Combo1.Clear
   Set POSTObj = WMIObj.InstancesOf("Win32_SerialPort")
   For Each COMPost In POSTObj
      '以下判断你的USB驱动名称进行识别
      Combo1.AddItem COMPost.Description & "(" & COMPost.DeviceID & ")"
      Combo1.ItemData(Combo1.ListCount - 1) = Int(Right(COMPost.DeviceID, Len(COMPost.DeviceID) - 3))
   Next
   Combo1.ListIndex = 0

[of123]

有这样的东东吗？我是搜索注册表的。

[用户 昵称]

发段vc的

//***********************
// 枚举所有的串口，以及名称
//***********************
int
EnumAllComm( TCHAR *buf )
{
    HKEY hkey;  
    int result;
	int i = 0;

	*buf = 0;

    result = RegOpenKeyEx( HKEY_LOCAL_MACHINE,
							_T( "Hardware\\DeviceMap\\SerialComm" ),
							NULL,
							KEY_READ,
							&hkey );

	if( ERROR_SUCCESS == result )   //   打开串口注册表   
	{   
		TCHAR portName[ 0x100 ], commName[ 0x100 ];
		DWORD dwLong, dwSize;

		do
		{   
			dwSize = sizeof( portName ) / sizeof( TCHAR );
			dwLong = dwSize;
			result = RegEnumValue( hkey, i, portName, &dwLong, NULL, NULL, ( LPBYTE )commName, &dwSize );
			if( ERROR_NO_MORE_ITEMS == result )
			{
				//   枚举串口
				break;   //   commName就是串口名字
			}
			_tcscpy( buf, commName );
			buf += ( _tcslen( buf ) + 1 );
			i++;   
		} while ( 1 );

		RegCloseKey( hkey );   
	}  

	*buf = 0;

	return i;
}

[cbm6666]

'*********************************读取注册表全部的串口

Private Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult As Long) As Long
Private Declare Function RegEnumValue Lib "advapi32.dll" Alias "RegEnumValueA" (ByVal hKey As Long, ByVal dwIndex As Long, ByVal lpValueName As String, lpcbValueName As Long, ByVal lpReserved As Long, lpType As Long, ByVal lpData As String, lpcbData As Long) As Long
Private Declare Function RegDeleteValue Lib "advapi32.dll" Alias "RegDeleteValueA" (ByVal hKey As Long, ByVal lpValueName As String) As Long
Const HKEY_LOCAL_MACHINE = &H80000002
Const REG_SZ = 1
Dim ComStr$()
Private Sub Command1_Click()
MsgBox GetAllPort
End Sub

Public Function GetAllPort() As String
On Error Resume Next
S = GetSerialPort(HKEY_LOCAL_MACHINE, "HARDWARE\DEVICEMAP\SERIALCOMM")
If ComStr(0) = "" Then Exit Function
GetAllPort = ""
For i = 0 To UBound(S)
GetAllPort = GetAllPort & S(i) & ","
Next i
End Function

Public Function GetSerialPort(RegAddr&, Items$) As String()
On Error Resume Next
Dim hKey&, S1$, S2$, L&, L1&
RegOpenKey RegAddr, Items, hKey
ReDim Preserve ComStr$(0)
ComStr(0) = "": i = 0: J = 0: Rtn = 0
Do
L = 1000: L1 = 1000
S1 = Space(L): S2 = Space(L)
Rtn = RegEnumValue(hKey, i, S1, L, 0, REG_SZ, S2, L1)
If Rtn = 0 Then
If InStr(S1, Chr(0)) > 0 And InStr(S2, Chr(0)) > 0 Then
S1 = UCase(Left(S1, InStr(S1, Chr(0)) - 1))
S2 = UCase(Left(S2, InStr(S2, Chr(0)) - 1))
If InStr(S2, "COM") > 0 Then
ReDim Preserve ComStr$(J)
ComStr(J) = S2
J = J + 1
End If
End If
End If
i = i + 1
Loop Until Rtn <> 0
GetSerialPort = ComStr()
End Function

[cbm6666]

'用 DOS 枚举您的机器串口配置端口号

'在DOS下运行必需使用短路径

Option Explicit
Private Declare Function GetShortPathName Lib "kernel32" Alias "GetShortPathNameA" (ByVal lpszLongPath As String, ByVal lpszShortPath As String, ByVal cchBuffer As Long) As Long
Dim AppDisk$, Fname$, aa$, t&
Private Sub Form_Load()
Me.Move (Screen.Width - Me.Width) \ 2, (Screen.Height - Me.Height) \ 2
Me.AutoRedraw = True
AppDisk = IIf(Right(App.Path, 1) = "\", App.Path, App.Path & "\")
AppDisk = GetShortName(AppDisk)
Fname = AppDisk & "test.txt"
If Dir(Fname) = "" Then
Open Fname For Output As #1
Close #1
End If
End Sub

Private Sub Command1_Click()
Call Shell("cmd /c mode >" & Fname, vbHide)
Open Fname For Input As #1
t = Timer
Do: DoEvents: Loop Until Timer > t + 1
While Not EOF(1)
Line Input #1, aa
If InStr(aa, "COM") > 0 Then Print aa
Wend
Close #1
End Sub

Public Function GetShortName(ByVal sLongFileName As String) As String
On Error Resume Next
Dim lRetVal&, sShortPathName$
sShortPathName = Space(255)
Call GetShortPathName(sLongFileName, sShortPathName, 255)
If InStr(sShortPathName, Chr(0)) > 0 Then
GetShortName = Mid(sShortPathName, 1, InStr(sShortPathName, Chr(0)) - 1)
Else
GetShortName = Trim(Mid(sShortPathName, 1))
End If
End Function

[贝隆]

有一个偏门方法，
使用API函数：CreateFile可以打开串口，如果成功打开那么返回值是：1，反之是：0 那么使用循环一个一个编号的操作，比如，连续打开了8个成功，第9个失败，那么就表示有8个串口。

[现在还是人类]

   Dim POSTObj As Object
   Dim COMPost As Object
   Combo1.Clear
   Set POSTObj = WMIObj.InstancesOf("Win32_SerialPort")
   For Each COMPost In POSTObj
      '以下判断你的USB驱动名称进行识别
      Combo1.AddItem COMPost.Description & "(" & COMPost.DeviceID & ")"
      Combo1.ItemData(Combo1.ListCount - 1) = Int(Right(COMPost.DeviceID, Len(COMPost.DeviceID) - 3))
   Next
   Combo1.ListIndex = 0

[布衣散人]

这么多好东西，20分太少了

[oken2]

谢谢大家！我去试试。