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Sending SCPI/GPIB commands over USB from C#

I'm trying to communicate with some test equipment from C# over SCPI. I managed to communicate with one device that is connected through TCP/IP by using this code example.
However, my other devices are connected through USB and I haven't find how to communicate with them over USB.
BTW, I found this question, and the link from the answer to the IVI-COM programming examples in C# document, but I couldn't apply the code samples (e.g. in section 5.4) because all of the IVI and VISA COM libraries I found (e.g. VisaComLib 5.5) has only interfaces and enums in it, and no concrete class that I can use...

If you install the visa driver from either NationalInstruments or Keysight, they do implement classes:
The one from NI:
FormattedIO488Class
ResourceManagerClass
VisaConflictTableManagerClass
To get a connection, you only need 1 and 2
As soon as you try to embed the interoptypes, you need to remove the 'Class' suffix, as described here
Here comes a sample snippet from Keysight (Application Note: 5989-6338EN)
Ivi.Visa.Interop.ResourceManager rm = new Ivi.Visa.Interop.ResourceManager();
Ivi.Visa.Interop.FormattedIO488 ioobj = new Ivi.Visa.Interop.FormattedIO488();
try
{
object[] idnItems;
ioobj.IO = (Ivi.Visa.Interop.IMessage)rm.Open("GPIB2::10::INSTR",
Ivi.Visa.Interop.AccessMode.NO_LOCK, 0, "");
ioobj.WriteString("*IDN ?", true);
idnItems = (object[])ioobj.ReadList(Ivi.Visa.Interop.IEEEASCIIType.ASCIIType_Any, ",");
foreach(object idnItem in idnItems)
{
System.Console.Out.WriteLine("IDN Item of type " + idnItem.GetType().ToString());
System.Console.Out.WriteLine("\tValue of item is " + idnItem.ToString());
}
}
catch(Exception e)
{
System.Console.Out.WriteLine("An error occurred: " + e.Message);
}
finally
{
try { ioobj.IO.Close(); }
catch { }
try
{
System.Runtime.InteropServices.Marshal.ReleaseComObject(ioobj);
}
catch { }
try
{
System.Runtime.InteropServices.Marshal.ReleaseComObject(rm);
}
catch { }
}

I'm using National Instruments VISA.
Add a reference to NationalInstruments.VisaNS and NationalInstruments.Common to your project.
Create a MessageBasedSession, see the following code:
string resourceName = "USB0::0x0957::0x0118::US56070667::INSTR"; // See NI MAX for resource name
var visa = new NationalInstruments.VisaNS.MessageBasedSession(resourceName);
visa.Write("*IDN?"); // write to instrument
string res = visa.ReadString(); // read from instrument
See as well https://stackoverflow.com/a/49388678/7556646.

Unable to format a drive (Unknown Error)

I'm using the WMI Volume ManagementObject to format a drive (Docs). If I try to do this from a non-elevated application, I get a result code of 3 (Access denied) which makes sense. Running the application as an administrator means I get a return code of 18 (Unknown Error).
ManagementObjectSearcher searcher = new ManagementObjectSearcher(
String.Format("select * from Win32_Volume WHERE DriveLetter = \"{0}\"", Drive));
foreach (ManagementObject vi in searcher.Get()) {
FormatResult result = (FormatResult)(int)(uint)vi.InvokeMethod("Format", new object[] { FileSystem, QuickFormat, ClusterSize, Label, EnableCompression });
if (result != FormatResult.Success) {
throw new FormatFailedException(String.Format("{0} (Error code {1})", result.ToString(), (int)result));
}
}
Parameters:
FileSystem: "NTFS"
Quick: false
ClusterSize: 4096
Label: "Test"
EnableCompression: false
I can format the drive with the above parameters through Explorer without any problems. How can I diagnose the issue and find out what's going on?
Since there seems to be some confusion, FormatResult is just an enum to simplify handling return codes...
enum FormatResult {
Success = 0,
UnsupportedFileSystem = 1,
IncompatibleMediaInDrive = 2,
AccessDenied = 3,
CallCanceled = 4,
...
UnknownError = 18
}
To give an idea of what I'm doing:
Since the docs mention that this method is usually called asynchronously, I've tried switching to an Async call with the same result (code available upon request). I've also tried various combinations of FileSystem (NTFS/FAT32), ClusterSize (including 0 to let the system pick a default), and Quick/Full formats. All give the same result of 18.
What am I missing?

virtual directory properties in c#

I did a quick search and got this link
From StackOverflow
I get this error message
"Unknown error (0x80005000)"
when it hits
bool canCreate = !(schema.Properties["Syntax"].Value.ToString().ToUpper() == "BOOLEAN");
My requirement is to create a virtual directory and set AccessRead, IsolationMode, Scripts and Executables, ApplicationProtection to medium.
Got it to work, here is the code:
Note: I still couldn't get it to work on windows 7, it throws the same error and the message includes reference to System.InterOp... At the moment I don't care about getting it to work on windows 7, I deployed it on windows 2003, it works.
public void CreateVirtualDirectory(string virtualdirectory, string physicalpath)
{
try
{
///check if path exists
if (!Directory.Exists(physicalpath))
{
Log(string.Format(#"CreateVirtualDirectory; Path not found - {0}", physicalpath));
return;
}
DirectoryEntry parent = new DirectoryEntry(string.Format("IIS://{0}/W3SVC/1/Root", Environment.MachineName));
foreach (System.DirectoryServices.DirectoryEntry v in parent.Children)
{
if (v.Name == virtualdirectory)
{
try
{
parent.Invoke("Delete", new string[] { v.SchemaClassName, virtualdirectory });
}
catch
{
}
}
}
DirectoryEntry newFolder = (DirectoryEntry)parent.Invoke("Create", "IIsWebVirtualDir", virtualdirectory);
newFolder.InvokeSet("Path", physicalpath);
newFolder.Invoke("AppCreate", false);
newFolder.InvokeSet("AppFriendlyName", virtualdirectory);
const int MEDIUM_POOL = 2;
newFolder.Properties["AccessRead"][0] = true;
newFolder.Properties["AccessExecute"][0] = true;
newFolder.Properties["AccessWrite"][0] = false;
newFolder.Properties["AccessScript"][0] = true;
newFolder.Properties["AuthNTLM"][0] = true;
newFolder.Properties["AppIsolated"].Clear();
newFolder.Properties["AppIsolated"].Add(MEDIUM_POOL);
newFolder.CommitChanges();
}
catch (Exception ex)
{
Log(string.Format(#"CreateVirtualDirectory '{0}' failed; {1}", virtualdirectory, ex.Message));
}
}

You're using DirectoryEntry to create websites which requires IIS Compat Mode to be installed/configured in IIS. That's compat mode for the IIS6 directory entry interfaces if you're on IIS7 or later.
If it's not installed, you'll get 80005000.
If you're on IIS7 or later (Windows Server 2008 or Vista and later), the newer (non-compat mode) approach is the new managed Microsoft.Web.Administration.
http://blogs.msdn.com/b/carlosag/archive/2006/04/17/microsoftwebadministration.aspx

Can I obtain the ClickOnce published Product Name from inside the application?

I have a ClickOnce Publish Name that is different from the assembly name. For discussion purposes, it is "App 6.0". I set it in the Properties for my project. Is there any way to get this value from inside the program?

Add a reference to Microsoft.Build.Tasks.v4.0.dll, then run this:
if (null != AppDomain.CurrentDomain.ActivationContext)
{
DeployManifest manifest;
using (MemoryStream stream = new MemoryStream(AppDomain.CurrentDomain.ActivationContext.DeploymentManifestBytes))
{
manifest = (DeployManifest)ManifestReader.ReadManifest("Deployment", stream, true);
}
// manifest.Product has the name you want
}
else
{
// not deployed
}
The DeployManifest can also provide other useful info from your manifest, like Publisher or SupportUrl.

The answer can be found in ClickOnce Run at Startup. Essentially, you use InPlaceHostingManager to get the ClickOnce manifest and read it. It bugs me that it is an asynchronous method, but this is the only thing that has worked thus far. Simplifications are much appreciated. See the webpage for a description of DeploymentDescription.
var inPlaceHostingManager = new InPlaceHostingManager(ApplicationDeployment.CurrentDeployment.UpdateLocation, false);
inPlaceHostingManager.GetManifestCompleted += ((sender, e) =>
{
try
{
var deploymentDescription = new DeploymentDescription(e.DeploymentManifest);
string productName = deploymentDescription.Product;
***DoSomethingToYour(productName);***
// - use this later -
//var commandBuilder = new StartMenuCommandBuilder(deploymentDescription);
//string startMenuCommand = commandBuilder.Command;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message + Environment.NewLine + ex.StackTrace);
}
});

ApplicationDeployment.UpdatedApplicationFullName Property

Getting location of file tnsnames.ora by code

How can I get the location of the tnsnames.ora file by code, in a machine with the Oracle client installed?
Is there a windows registry key indicating the location of this file?

Some years ago I had the same problem.
Back then I had to support Oracle 9 and 10 so the code only takes care of those versions, but maybe it saves you from some research.
The idea is to:
search the registry to determine the oracle client version
try to find the ORACLE_HOME
finally get the tnsnames from HOME
public enum OracleVersion
{
Oracle9,
Oracle10,
Oracle0
};
private OracleVersion GetOracleVersion()
{
RegistryKey rgkLM = Registry.LocalMachine;
RegistryKey rgkAllHome = rgkLM.OpenSubKey(#"SOFTWARE\ORACLE\ALL_HOMES");
/*
* 10g Installationen don't have an ALL_HOMES key
* Try to find HOME at SOFTWARE\ORACLE\
* 10g homes start with KEY_
*/
string[] okeys = rgkLM.OpenSubKey(#"SOFTWARE\ORACLE").GetSubKeyNames();
foreach (string okey in okeys)
{
if (okey.StartsWith("KEY_"))
return OracleVersion.Oracle10;
}
if (rgkAllHome != null)
{
string strLastHome = "";
object objLastHome = rgkAllHome.GetValue("LAST_HOME");
strLastHome = objLastHome.ToString();
RegistryKey rgkActualHome = Registry.LocalMachine.OpenSubKey(#"SOFTWARE\ORACLE\HOME" + strLastHome);
string strOraHome = "";
object objOraHome = rgkActualHome.GetValue("ORACLE_HOME");
string strOracleHome = strOraHome = objOraHome.ToString();
return OracleVersion.Oracle9;
}
return OracleVersion.Oracle0;
}
private string GetOracleHome()
{
RegistryKey rgkLM = Registry.LocalMachine;
RegistryKey rgkAllHome = rgkLM.OpenSubKey(#"SOFTWARE\ORACLE\ALL_HOMES");
OracleVersion ov = this.GetOracleVersion();
switch(ov)
{
case OracleVersion.Oracle10:
{
string[] okeys = rgkLM.OpenSubKey(#"SOFTWARE\ORACLE").GetSubKeyNames();
foreach (string okey in okeys)
{
if (okey.StartsWith("KEY_"))
{
return rgkLM.OpenSubKey(#"SOFTWARE\ORACLE\" + okey).GetValue("ORACLE_HOME") as string;
}
}
throw new Exception("No Oracle Home found");
}
case OracleVersion.Oracle9:
{
string strLastHome = "";
object objLastHome = rgkAllHome.GetValue("LAST_HOME");
strLastHome = objLastHome.ToString();
RegistryKey rgkActualHome = Registry.LocalMachine.OpenSubKey(#"SOFTWARE\ORACLE\HOME" + strLastHome);
string strOraHome = "";
object objOraHome = rgkActualHome.GetValue("ORACLE_HOME");
string strOracleHome = strOraHome = objOraHome.ToString();
return strOraHome;
}
default:
{
throw new Exception("No supported Oracle Installation found");
}
}
}
public string GetTNSNAMESORAFilePath()
{
string strOracleHome = GetOracleHome();
if (strOracleHome != "")
{
string strTNSNAMESORAFilePath = strOracleHome + #"\NETWORK\ADMIN\TNSNAMES.ORA";
if (File.Exists(strTNSNAMESORAFilePath))
{
return strTNSNAMESORAFilePath;
}
else
{
strTNSNAMESORAFilePath = strOracleHome + #"\NET80\ADMIN\TNSNAMES.ORA";
if (File.Exists(strTNSNAMESORAFilePath))
{
return strTNSNAMESORAFilePath;
}
else
{
throw new SystemException("Could not find tnsnames.ora");
}
}
}
else
{
throw new SystemException("Could not determine ORAHOME");
}
}

On Windows, the most likely locations are either %ORACLE_HOME%/network/admin or %TNS_ADMIN% (or the TNS_ADMIN registry setting). These two cover almost every installation.
Of course it is possible to have a working Oracle client without this file. Oracle has bewildering array of networking options, and there are plenty of ways to achieve a working setup with using TNSNAMES. Depending on what you are trying to achieve here, your first port of call might be the sqlnet.ora file, which is also found in %ORACLE_HOME%/network/admin. This should contain a line that looks something like this:
NAMES.DIRECTORY_PATH= (LDAP, TNSNAMES, HOSTNAME)
TNSNAMES means it will use the TNSNAMES.ora file (second in this case). LDAP and HOSTNAME are alternate ways of resolving the database. If there is no TNSNAMES the TNSNAMES.ora file will be ignored if it exists in the right place.
In C# / .NET this should get you the environment variables:
Environment.GetEnvironmentVariable("ORACLE_HOME");
Environment.GetEnvironmentVariable("TNS_ADMIN");

List<string> logicalDrives = Directory.GetLogicalDrives().ToList();
List<string> result = new List<string>();
foreach (string drive in logicalDrives)
{
Console.WriteLine("Searching " + drive);
DriveInfo di = new DriveInfo(drive);
if(di.IsReady)
result = Directory.GetFiles(drive, "tnsnames.ora", SearchOption.AllDirectories).ToList();
if (0 < result.Count) return;
}
foreach (string file in result) { Console.WriteLine(result); }

According to the net that depends on the version of Oracle and the working directory of the SQL*Plus process. This first link tells you the environment variable that specifies the base path for some versions (7, 8, 9i) of Oracle. If you use a different one, I'm sure there's a similar way to get to the system directory.
If you spread versions of these files all over the place though and rely on the "look for a local tnsnames.ora first" behaviour of the client, then I guess you're out of luck.

I'm not a C# or a Windows guy for that matter so hopefully this helps. The tnsnames.ora file should be located in:
ORACLE_HOME\network\admin
If an alternate location has been specified, it should be available via the TNS_ADMIN registry key.
See this link for more information on how Oracle handles tns names on Windows.