I know it is possible to compile c# code at runtime using C#, with CSharpCodeProvider and CodeDom.
Is it possible to compile also Java? If it isn't, is there any alternative?
I want my application to be able to compile C# and Java code.
You will need to have JDK (or equivalent installed) on the system performing the compilation
You will need to invoke the Java compiler
You will presumably need to use the compiled code using the Java Runtime (or equivalent)
Method A:
The easiest way to both use the compiler and use the compiled code would be trough Process.Start as mentioned in Kieren's answer. This is easy provided you have the necessary components.
//add this either atusing System.Diagnostics;
static void CompileJava(string javacPathName, string javaFilePathName, string commandLineOptions = "")
{
var startInfo = new ProcessStartInfo();
startInfo.CreateNoWindow = true;
startInfo.UseShellExecute = false;
startInfo.FileName = javacPathName;
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
startInfo.Arguments = commandLineOptions + " " + javaFilePathName;
try {
using (var javacProcess = Process.Start(startInfo))
{
javacProcess.WaitForExit();
}
}
catch(Exception e)
{
// do something e.g. throw a more appropriate exception
}
}
Method B:
If you require deeper integration, you could try the native linking method (i.e. use .NET and the Java native interfaces for the two to interoperate without invoking external processes). The pre-requisites are the same as with Method A. The investment required is much higher and you should only consider this if there are specific performance or other constraints Method A cannot meet.
You can find some information by following the links below:
From the C# side: http://blogs.msdn.com/b/texblog/archive/2007/04/05/linking-native-c-into-c-applications.aspx
From the Java side: http://docs.oracle.com/javase/6/docs/technotes/guides/jni/
To expand on what driis and ppeterka are saying, there's no built-in way since Java isn't a .NET language (J# was close but doesn't exist anymore). You'd need to use Process.Start to fire up the java compiler.
Your specific situation may require it, but Java isn't built for this, it is built to be compiled at compile time, not at runtime. While Miltiadis Kokkonidis's answer works, it's probably best to either use a different language that fits your problem better, or use the languages strengths for the situation at hand, rather then try to squeeze it to fit places it doesn't want to go.
Related
When you run Get-ExecutionPolicy in PowerShell, it gets the effective execution policy. I need to know the best way to get that information in C#. I don't need to know how to change it like many other questions about PowerShell Execution Policy, I just need to know how to get it in C#.
Note:
PowerShell execution policies apply only on Windows.
With respect to Windows, the answer below covers both PowerShell editions.
It can be inferred from the docs that boxdog pointed to in a comment, but to spell it out:
using System;
using System.Management.Automation;
namespace demo
{
class ConsoleApp {
static void Main() {
using (var ps = PowerShell.Create()) {
var effectivePolicy = ps.AddCommand("Get-ExecutionPolicy").Invoke()[0].ToString();
ps.Commands.Clear();
Console.WriteLine("Effective execution policy: " + effectivePolicy);
}
}
}
}
Note:
The above assumes that you're using the PowerShell SDK - see this answer for the appropriate NuGet package to add to your project.
If you're using a PowerShell (Core) 7+ SDK, additional considerations apply:
On Unix-like platforms, execution policies fundamentally do not apply (Unrestricted is reported, though in effect it is Bypass), so the following applies to Windows only:
The LocalMachine scope of any - by definition install-on-demand - PowerShell (Core) 7+ version does not apply; only - if defined - the CurrentUser and GPO-based policies (which preempt the former) do.
On Windows:
In the absence of a relevant execution policy being defined, Restricted is the default, which categorically prevents execution of script files (.ps1).
If your application needs to execute .ps1 files when hosting the PowerShell SDK, for predictable behavior it is best to set the execution policy, for the current process only, as shown in this answer.
The most elegant solution would probably be to get the ExecutionPolicy registry key in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PowerShell\1\ShellIds\Microsoft.PowerShell. For this solution to work, your program needs to be running on the same architecture (x64 or x86) as the operating system it's running on or it won't be able to see the registry key. Code to do this would look something like this:
using Microsoft.Win32
...
string executionPolicy = Registry.GetValue(#"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PowerShell\1\ShellIds\Microsoft.PowerShell", "ExecutionPolicy", null)?.ToString();
If for any reason you can't do the first solution, the second way I would recommend is by using the System.Management.Automation.PowerShell NuGet package. This method would look something like this:
using(var ps = PowerShell.Create()){
ps.AddScript("Get-ExecutionPolicy");
Collection<PSObject> output = ps.Invoke();
Console.WriteLine($"Execution policy is {output[0]}")
}
If you really don't want to add an extra NuGet package to your project, there is another, but quite a bit messier way of doing this using System.Diagnostics.Process and it's output stream. It would look something like this:
var procInfo = new ProcessStartInfo("powershell.exe", "-Command \"Get-ExecutionPolicy\"")
{
CreateNoWindow = true,
UseShellExecute = false,
RedirectStandardOutput = true
};
var proc = new Process
{
StartInfo = procInfo
};
proc.OutputDataReceived += Proc_OutputDataReceived;
proc.Start();
proc.BeginOutputReadLine();
Console.ReadLine();
...
private static void Proc_OutputDataReceived(object sender, DataReceivedEventArgs e)
{
if (!string.IsNullOrWhiteSpace(e.Data))
Console.WriteLine($"Execution policy is {e.Data}");
}
I have a Python backend running machine learning algorithms. I want to use the same backend for both an Excel plugin (C#) and a website. I want both interfaces to send my training data (thousands of lines of numbers in arrays) to the same Python application and retrieve the results in the form of another array up to a few thousand lines.
The website would fetch data from a SQL database and send that data to Python, while the Excel plugin would take the data that is in the current worksheet and send that data to Python. I need to be able to create numpy arrays in Python before continuing to process the data. Note that the website would be running on the same machine where the Python application resides. I still haven't decided what I will use to code the website, but I was leaning towards Node.js.
I have done some research and found a few options:
1- Named pipes
2- Sockets
3- RPC server such as gRPC or XML-RPC.
4- Writing the data to a file and reading it back in Python
5- Web Service
Note: I would need the Python "server" to be stateful and keep the session running between calls. So I would need to have a kind of daemon running, waiting for calls.
Which one would you experts recommend and why? I need flexibility to handle several parameters and also large arrays of numbers. Using IronPython is not an option because I am running Keras on Python, which apparently does not support IronPython.
I had the same problem recently.
I used a named pipe to transport data from python to my c# server, hope it helps you.
Python:
import win32pipe, win32file
class PipeServer():
def __init__(self, pipeName):
self.pipe = win32pipe.CreateNamedPipe(
r'\\.\pipe\\'+pipeName,
win32pipe.PIPE_ACCESS_OUTBOUND,
win32pipe.PIPE_TYPE_MESSAGE | win32pipe.PIPE_READMODE_MESSAGE | win32pipe.PIPE_WAIT,
1, 65536, 65536,
0,
None)
#Carefull, this blocks until a connection is established
def connect(self):
win32pipe.ConnectNamedPipe(self.pipe, None)
#Message without tailing '\n'
def write(self, message):
win32file.WriteFile(self.pipe, message.encode()+b'\n')
def close(self):
win32file.CloseHandle(self.pipe)
t = PipeServer("CSServer")
t.connect()
t.write("Hello from Python :)")
t.write("Closing now...")
t.close()
For this code to work you need to install pywin32 (best choice is from binarys): https://github.com/mhammond/pywin32
C#-Server:
using System;
using System.IO;
using System.IO.Pipes;
class PipeClient
{
static void Main(string[] args)
{
using (NamedPipeClientStream pipeClient =
new NamedPipeClientStream(".", "CSServer", PipeDirection.In))
{
// Connect to the pipe or wait until the pipe is available.
Console.Write("Attempting to connect to pipe...");
pipeClient.Connect();
Console.WriteLine("Connected to pipe.");
Console.WriteLine("There are currently {0} pipe server instances open.",
pipeClient.NumberOfServerInstances);
using (StreamReader sr = new StreamReader(pipeClient))
{
// Display the read text to the console
string temp;
while ((temp = sr.ReadLine()) != null)
{
Console.WriteLine("Received from server: {0}", temp);
}
}
}
Console.Write("Press Enter to continue...");
Console.ReadLine();
}
}
You can use Python for .NET (Python.NET). It may require some changes to your code, but then it should work very well, once everything is in good shape.
Python.NET allows two-way communication between CPython and CLR.
Let me give you a neat and quick recipe, in the form of example code.
There are basically two ways to tie python in the backend of C# (or a C# winform app or gui or something similar).
Method1: Iron Python. In this method you install a .net package in your visual studio called IronPython. I would not prefer this, because assuming your machine learning model uses keras or a lot of other libraries. It would be another quest to get you installations ready and working in IronPython. And most importantly, it is not as good as your common virtual env or conda environment.
Method2: (The Good Method): Create a Custom Process in your C# that takes arguments from your GUI, knows the path to your script and your python env. Using all these things, it calls your python code exactly the way you would call it in your terminal and pass arguments to it.
Now the tasty example code (I have used this simple trick and it always helps make my black screen python stuff look good with the cover of C# apps).
Python Part
import sys
a = sys.argv[1]
b = sys.argv[2]
print("The Sum = ", float(a)+float(b))
The C# Part
So here is the python process/function that you need to call on the click event of your sum button in the application
static void PythonProcess()
{
//1) Create Process Info
var psi = new ProcessStartInfo();
//Conda Env Path
psi.FileName = #"C:\Users\jd\.conda\pkgs\py\python.exe";
//2) Provide Script and the Arguments
var script = #"C:\Users\jd\Desktop\script.py";
var a = "15";
var b = "18";
psi.Arguments = $"\"{script}\" \"{a}\" \"{b}\"";
//3) Process Configuration
psi.UseShellExecute = false;
psi.CreateNoWindow = true;
psi.RedirectStandardOutput = true;
psi.RedirectStandardError = true;
//4) Execute Process and get Output.
var errors = "";
var results = "";
using(var process = Process.Start(psi))
{
errors = process.StandardError.ReadToEnd();
results = process.StandardOutput.ReadToEnd();
}
//5) Display Output
Console.WriteLine("ERRORS: ");
Console.WriteLine(errors);
Console.WriteLine();
Console.WriteLine("RESULTS: ");
Console.WriteLine(results);
}
Calling Python from C# is easily possible via Pyrolite where your Python code is running as a Pyro4 server. It should be fast enough to handle "large arrays of numbers" however you didn't specify any performance constraints.
I had the same issue and seem to end up with named pipes. Here is a nice example of how to set it up to talk C# => Python, assuming C# is the server.
It can use the same way to talk back or just Python.net to call directly through CLR as shown here. I use the latter.
There is a Resource Hacker program which allow to change the resources in the other win32(64) dll and exe files.
I need to do the same thing, but programmaticaly. Is it possible to do it using .Net framework? What is the good starting point to do it?
You must use the BeginUpdateResource, UpdateResource and EndUpdateResource WinApi functions, try this page to check the pinvoke .Net signature of these functions, also you can check this project ResourceLib.
The author points to another tool "XN Resource Editor" which comes with source code (although Delphi, not .NET).
This should be enough to see which functions being used and use the .NET equivalent of them.
Take a look at Anolis.Resourcer. It seems to be the thing you need
A ResHacker clone developed as a testbed for Anolis.Core and to replace ResHacker (because ResHacker doesn't support x64, XN Resource Editor (ResHacker's spiritual sequel) doesn't support multiple-language resources and crashes a lot, and other utilities rest cost actual money. It has a powerful yet simplified UI that doesn't duplicate commands or confuse the users with special-case handlers (which ResHacker and XN have in spades).
Note that none of these will work if you're dealing with signed EXEs or DLLs.
Well, as I see it is not easy task, so I'll use command line interface of Resource Hacker.
If you want to do it straight from .NET, there is a library called Ressy exactly for this purpose. It provides both low-level operations on resources (i.e. working with raw byte streams), as well as high-level (i.e. replacing icons, manifests, version info, etc.).
Add or overwrite a resource:
using Ressy;
var portableExecutable = new PortableExecutable("C:/Windows/System32/notepad.exe");
portableExecutable.SetResource(
new ResourceIdentifier(
ResourceType.Manifest,
ResourceName.FromCode(1),
new Language(1033)
),
new byte[] { 0x01, 0x02, 0x03 }
);
Get resource data:
using Ressy;
var portableExecutable = new PortableExecutable("C:/Windows/System32/notepad.exe");
var resource = portableExecutable.GetResource(new ResourceIdentifier(
ResourceType.Manifest,
ResourceName.FromCode(1),
new Language(1033)
));
var resourceData = resource.Data; // byte[]
var resourceString = resource.ReadAsString(Encoding.UTF8); // string
Set file icon:
using Ressy;
using Ressy.HighLevel.Icons;
var portableExecutable = new PortableExecutable("C:/Windows/System32/notepad.exe");
portableExecutable.SetIcon("new_icon.ico");
See the readme for more examples.
I want to be able to specify how many clients do I want opened, and be able to manually switch between the windows after they're opened- meaning "streaming in background" (if such a thing is possible? ) won't do here.
I need to specify different inputs for the different clients as well.
Additionally -and this is the part I'm totally clueless about as it's VLC-specific - I need the clients to be logging some info re:the stream they're receiving, so as to be able to determine that it has been received completely etc -such as frame rate/total frames' number or similar.
I'd appreciate helpful suggestions for
running the instances+ controlling
them
getting info about
the stream
Language-wise - I know Java, some C#, and wouldn't mind learning some new language for this purpose if it's a better solution .
Thanks!
Depending on your version of VLC, you may need to enable an option to run multiple instances. See here: http://wiki.videolan.org/How_to_play_multiple_instances_of_VLC
It does sound like a 'run windows processes in a loop' thing, which you could do several ways.
You could make a windows batch file (.bat):
"C:\path\to\vlc.exe" -vvv "http://www.whatever.com/mystream.mms"
"C:\path\to\vlc.exe" -vvv "http://www.whatever.com/mystream2.mms"
"C:\path\to\vlc.exe" -vvv "C:\music\whatever.mp3"
Or you could use a real programming language and perhaps open a variable number of instances... C# for example:
using System.Diagnostics;
...
foreach (string stream in streamList) {
Process myProc = new Process();
string myCmd = #"C:\path\to\vlc.exe";
string myArgs = "-vvv \"" + stream + "\"";
ProcessStartInfo myStart = new ProcessStartInfo(myCmd, myArgs);
myStart.UseShellExecute = false;
myProc.StartInfo = myStart;
myProc.Start();
}
See this page for a full list of VLC command line options: http://www.videolan.org/doc/vlc-user-guide/en/ch04.html
Hope this helps.
You'll either need to run several processes (as above) or hook somehow into libvlc and instruct it to start up several players.
A good demo of this is the python wrapper to libvlc--I think--it shows how to sample to know where the stream is--however I've never tried it with multiple things running at the same time but I think it would work.
Another option might be something like http://wiki.videolan.org/Mosaic
just downloaded ActivePerl. I want to embed the perl interpreter in a C# application (or at least call the perl interpreter from C#). I need to be able to send send out data to Perl from C#, then receive the output back into C#.
I just installed ActivePerl, and added MS Script Control 1.0 as a reference. I found this code on the internet, but am having trouble getting it to work.
MSScriptControl.ScriptControlClass Interpreter = new MSScriptControl.ScriptControlClass();
Interpreter.Language = #"ActivePerl";
string Program = #"reverse 'abcde'";
string Results = (string)Interpreter.Eval(Program);
return Results;
Originally, it had 'PerlScript' instead of 'ActivePerl', but neither work for me. I'm not entirely sure what Interpreter.Language expects. Does it require the path to the interpreter?
Solved... I'm not sure how, but when I changed it back to PerlScript it works now. Still, I would like to know if MSScript Control is using ActivePerl or another interpreter.
You can run an external program as Maxwell suggests, in which case the external program can be Perl or anything else. It might be easier to use temp files to send the input data and get the output, but that depends on how the external program expects to get its data.
The alternative, which is what I think you're looking for, is to use the PerlNET compiler that comes with ActiveState's Perl Dev Kit. It lets you add a class wrapper around the Perl code so you can expose it to C# just like any C# class. It's fairly simple to use; you add POD comments to your Perl code to specify the method names and signatures to expose, including type information, then you compile your Perl module into a DLL .NET assembly. Once that's done you can reference the assembly from any .NET program, construct an object from your Perl class, and call its methods.
I am not sure about the script control but I have done a similar thing where I had to 'embed' spamassasin (which is a Perl program). I basically used the Process to do the job. Something along the lines of:
var proc = new Process
{
StartInfo =
{
FileName = "perl",
WorkingDirectory = HttpRuntime.AppDomainAppPath,
Arguments = " myscript.pl arg1 arg2",
RedirectStandardOutput = true,
RedirectStandardError = true,
RedirectStandardInput = true,
UseShellExecute = false
}
};
proc.Start();
proc.StandardInput.BaseStream.Write... // feed STDIN
proc.StandardOutput.Read... // Read program output
var procStdErr = proc.StandardError.ReadToEnd(); // errors
proc.StandardError.Close();
proc.StandardOutput.Close();
proc.WaitForExit(3000);
int exitCode = proc.ExitCode;
proc.Close();
This obviously not just Perl specific and it has the process creation overhead, so if you are running your script too often probably you need to think of a different solution.