1，使用Win32_TCPIPPrinterPort来获取打印机的 TCP IP端口
/// <summary>
/// 获取本地打印机TCPIP名字192.168.0.1 Win32_TCPIPPrinterPort
/// </summary>
/// <returns></returns>
private List<string> GetLocalPrinterTcpIpList()
{
List<string> listCom = new List<string>();
ManagementScope scope = new ManagementScope(@”\root\cimv2″);
//获取打印机IP名字 192.168.0.1 Win32_TCPIPPrinterPort
var vComs = new ManagementObjectSearcher(scope, new ObjectQuery(“select * from Win32_TCPIPPrinterPort”)).Get();
foreach (var vCom in vComs)
{
listCom.Add(vCom.Properties[“Name”].Value.ToString());
}
return listCom;
}
2，使用注册表方式来获取打印机的COM口，LPT端口，以及本地端口
/// <summary>
/// 获取打印机COM LPT Local三种端口
/// </summary>
/// <returns></returns>
private List<string> GetPrinterComLptLocalPort()
{
List<string> listRet = new List<string>();
string strLocalPortPath = @”SOFTWARE\Microsoft\Windows NT\CurrentVersion\Ports”;
RegistryKey localMachineReg = Registry.LocalMachine;
RegistryKey reg = null;
reg = localMachineReg.OpenSubKey(strLocalPortPath, true); //用于读写
foreach (var vItem in reg.GetValueNames())
{
if (vItem.Contains(“Ne”) && vItem.LastIndexOf(‘:’) == vItem.Length – 1) //Ne开头的并且是冒号结尾的不加入端口中
{
continue;
}
listRet.Add(vItem);
}
localMachineReg.Close();
return listRet;
}
3，使用Win API获取（上述两种方式获取不是很全面)，使用Win API 可以获取到LPT，COM ，USB等和在windows控制面板中 打印机端口列表看到的是一样的
class Myclass
{
//PortType enum
//struct for PORT_INFO_2
[StructLayout(LayoutKind.Sequential)]
public struct PORT_INFO_2
{
public string pPortName;
public string pMonitorName;
public string pDescription;
public PortType fPortType;
internal int Reserved;
}
[Flags]
public enum PortType : int
{
write = 0x1,
read = 0x2,
redirected = 0x4,
net_attached = 0x8
}
//Win32 API
[DllImport(“winspool.drv”, EntryPoint = “EnumPortsA”, CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
public static extern int EnumPorts(string pName, int Level, IntPtr lpbPorts, int cbBuf, ref int pcbNeeded, ref int pcReturned);
/// <summary>
/// method for retrieving all available printer ports
/// </summary>
/// <returns>generic list populated with post names (i.e; COM1, LTP1, etc)</returns>
public List<string> GetPortNames()
{
//variables needed for Win32 API calls
int result; int needed = 0; int cnt = 0; IntPtr buffer = IntPtr.Zero; IntPtr port = IntPtr.Zero;
//list to hold the returned port names
List<string> ports = new List<string>();
//new PORT_INFO_2 for holding the ports
PORT_INFO_2[] portInfo = null;
//enumerate through to get the size of the memory we need
result = EnumPorts(“”, 2, buffer, 0, ref needed, ref cnt);
try
{
//allocate memory
buffer = Marshal.AllocHGlobal(Convert.ToInt32(needed + 1));
//get list of port names
result = EnumPorts(“”, 2, buffer, needed, ref needed, ref cnt);
//check results, if 0 (zero) then we got an error
if (result != 0)
{
//set port value
port = buffer;
//instantiate struct
portInfo = new PORT_INFO_2[cnt];
//now loop through the returned count populating our array of PORT_INFO_2 objects
for (int i = 0; i < cnt; i++)
{
portInfo[i] = (PORT_INFO_2)Marshal.PtrToStructure(port, typeof(PORT_INFO_2));
port = (IntPtr)(port.ToInt64() + Marshal.SizeOf(typeof(PORT_INFO_2)));
}
port = IntPtr.Zero;
}
else
throw new Win32Exception(Marshal.GetLastWin32Error());
//now get what we want. Loop through al the
//items in the PORT_INFO_2 Array and populate our generic list
for (int i = 0; i < cnt; i++)
{
ports.Add(portInfo[i].pPortName);
}
//sort the list
ports.Sort();
return ports;
}
catch (Exception ex)
{
Console.WriteLine(string.Format(“Error getting available ports: {0}”, ex.Message));
Console.ReadLine();
return null;
}
finally
{
if (buffer != IntPtr.Zero)
{
Marshal.FreeHGlobal(buffer);
buffer = IntPtr.Zero;
port = IntPtr.Zero;
}
}
}
}