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Python.Net - How to run python script from file(.Py)

How to run .py files and call function by using python.Net library.
i have tried below code but it is not running.
using (Py.GIL()){
var fromFile = PythonEngine.Compile(null, #"C:\PycharmProjects\pythonenet\main.py", RunFlagType.File);
fromFile.InvokeMethod("replace");//
}
main.py file:
import re
def replace():
print(re.sub(r"\s","*","Python is a programming langauge"))
When i try to run from string it is working.
using (Py.GIL()){
string co = #"def someMethod():
print('This is from static script')";
var fromString = PythonEngine.ModuleFromString("someName", co);
fromString.InvokeMethod("someMethod");
}

Finally i ended up with the following solution.
using (Py.GIL()){
dynamic os = Py.Import("os");
dynamic sys = Py.Import("sys");
sys.path.append(os.path.dirname(os.path.expanduser(filePath)));
var fromFile = Py.Import(Path.GetFileNameWithoutExtension(filePath));
fromFile.InvokeMethod("replace");
}

How do I import a third-party IronPython module in .NET?

I am C# developer and I have to use an IronPython library in the .NET framework. I tested every class in Python and it's working but I am not sure how to call the library in a C# class.
When I try to call the library, I am getting a 'LightException' object has no attribute client error.
I have added lib, -x:Full frame and also all modules in the lib folder.
Here is the C# code I am using to call the Python library:
Console.WriteLine("Press enter to execute the python script!");
Console.ReadLine();
var options = new Dictionary<string, object>();
options["Frames"] = true;
options["FullFrames"] = true;
//var py = Python.CreateEngine(options);
//py.SetSearchPaths(paths);
ScriptEngine engine = Python.CreateEngine(options);
ICollection<string> paths = engine.GetSearchPaths();
string dir = #"C:\Python27\Lib\";
paths.Add(dir);
string dir2 = #"C:\Python27\Lib\site-packages\";
paths.Add(dir2);
engine.SetSearchPaths(paths);
ScriptSource source = engine.CreateScriptSourceFromFile(#"C:\Users\nikunjmange\Source\Workspaces\Visage Payroll\VisagePayrollSystem\VisagePayrollSystem\synapsepayLib\synapse_pay-python-master\synapse_pay\resources\user.py");
ScriptScope scope = engine.CreateScope();
source.Execute(scope);
dynamic Calculator = scope.GetVariable("User");
dynamic calc = Calculator();
string inputCreate = "nik12#gmail.com";
string result = calc.create(inputCreate);

The error is misleading because of a bug in IronPython 2.7.5. It should be an ImportError.
Don't add the normal CPython stdlib; it's not compatible with IronPython. Use IronPython's stdlib instead.
If you have an import of import a.b as c that's probably the culprit; either a or b does not exist but IronPython mucks up the error reporting.

Embedding Python in C# via resources

I have been working on a problem for a while now which I cannot seem to resolve so I need some help! The problem is that I am writing a program in C# but I require a function from a Python file I created. This in itself is no problem:
...Usual Stuff
using IronPython.Hosting;
using IronPython.Runtime;
using Microsoft.Scripting;
using Microsoft.Scripting.Hosting;
namespace Program
{
public partial class Form1 : Form
{
Microsoft.Scripting.Hosting.ScriptEngine py;
Microsoft.Scripting.Hosting.ScriptScope s;
public Form1()
{
InitializeComponent();
py = Python.CreateEngine(); // allow us to run ironpython programs
s = py.CreateScope(); // you need this to get the variables
}
private void doPython()
{
//Step 1:
//Creating a new script runtime
var ironPythonRuntime = Python.CreateRuntime();
//Step 2:
//Load the Iron Python file/script into the memory
//Should be resolve at runtime
dynamic loadIPython = ironPythonRuntime.;
//Step 3:
//Invoke the method and print the result
double n = loadIPython.add(100, 200);
numericUpDown1.Value = (decimal)n;
}
}
}
However, this requires for the file 'first.py' to be wherever the program is once compiled. So if I wanted to share my program I would have to send both the executable and the python files which is very inconvenient. One way I thought to resolve this is by adding the 'first.py' file to the resources and running from there... but I don't know how to do this or even if it is possible.
Naturally the above code will not work for this as .UseFile method takes string arguments not byte[]. Does anyone know how I may progress?

Lets start with the simplest thing that could possibly work, you've got some code that looks a little like the following:
// ...
py = Python.CreateEngine(); // allow us to run ironpython programs
s = py.CreateScope(); // you need this to get the variables
var ironPythonRuntime = Python.CreateRuntime();
var x = py.CreateScriptSourceFromFile("SomeCode.py");
x.Execute(s);
var myFoo = s.GetVariable("myFoo");
var n = (double)myFoo.add(100, 200);
// ...
and we'd like to replace the line var x = py.CreateScriptSourceFromFile(... with something else; If we could get the embedded resource as a string, we could use ScriptingEngine.CreateScriptSourceFromString().
Cribbing this fine answer, we can get something that looks a bit like this:
string pySrc;
var resourceName = "ConsoleApplication1.SomeCode.py";
using (var stream = System.Reflection.Assembly.GetExecutingAssembly()
.GetManifestResourceStream(resourceName))
using (var reader = new System.IO.StreamReader(stream))
{
pySrc = reader.ReadToEnd();
}
var x = py.CreateScriptSourceFromString(pySrc);

How do I execute a script with Roslyn in End User Preview

I'm trying to play around with the end user preview of roslyn and would like to execute a simple script. What I would like to do is something like:
static void Main(string[] args)
{
// Is this even valid?
var myScript = "int x = 5; int y = 6; x + y;";
// What should I do here?
var compiledScript = Something.Compile(myScript);
var result = compiledScript.Execute(myScript);
Console.WriteLine(result);
}
Can someone point to some resources and/or tell me which nuget packages to install to make this happen. I've installed the Microsoft.CodeAnalysis, but can't figure out if it doable with just that, I feel like I'm missing something.

The scripting APIs which would allow you to do this very easily were (temporarily) removed in the latest preview. You can still compile a script, emit and load the assembly and invoke its entry point by doing something along the lines of
public static class Program
{
public static void Main(string[] args)
{
var assemblyPath = Path.GetDirectoryName(typeof(object).Assembly.Location);
var defaultReferences = new[] { "mscorlib.dll", "System.dll", "System.Core.dll" };
var script = #"using System;
public static class Program
{
public static void Main(string[] args)
{
Console.WriteLine(""Hello {0}"", args[0]);
}
}";
// Parse the script to a SyntaxTree
var syntaxTree = CSharpSyntaxTree.ParseText(script);
// Compile the SyntaxTree to a CSharpCompilation
var compilation = CSharpCompilation.Create("Script",
new[] { syntaxTree },
defaultReferences.Select(x => new MetadataFileReference(Path.Combine(assemblyPath, x))),
new CSharpCompilationOptions(OutputKind.ConsoleApplication));
using (var outputStream = new MemoryStream())
using (var pdbStream = new MemoryStream())
{
// Emit assembly to streams.
var result = compilation.Emit(outputStream, pdbStream: pdbStream);
if (!result.Success)
{
return;
}
// Load the emitted assembly.
var assembly = Assembly.Load(outputStream.ToArray(), pdbStream.ToArray());
// Invoke the entry point.
assembly.EntryPoint.Invoke(null, new object[] { new[] { "Tomas" } });
}
}
}
It will output Hello Tomas in the console :)

It appears that in the April 2014 release, scripting has been temporarily removed:
What happened to the REPL and hosting scripting APIs?
The team is reviewing the designs of these components that you saw in
previous CTPs, before re-introducing the components again. Currently
the team is working on completing the language semantics of
interactive/script code.

Create System.Windows.Media.Color in IronPython

Im using IronPython and i try to instantiate a color from script and return it.
I got this method and send in this string as an argument
#"
from System.Windows.Media import Color
c = Color()
c.A = 100
c.B = 200
c.R = 100
c.G = 150
c
");
_python = Python.CreateEngine();
public dynamic ExectureStatements(string expression)
{
ScriptScope scope = _python.CreateScope();
ScriptSource source = _python.CreateScriptSourceFromString(expression);
return source.Execute(scope);
}
When I run this code I get
$exception {System.InvalidOperationException: Sequence contains no matching element
at System.Linq.Enumerable.First[TSource](IEnumerable`1 source, Func`2 predicate).. etc.
I can not figure out how to get this to work, so please help me.

I won't know for sure until I see either more of your source or the full stack, but I would guess you're missing having the python engine include a reference to the necessary WPF assemblies (PresentationCore for System.Windows.Media.Color AFAICT).
Depending on whether you care about the C# caller needing a reference to the same library, you can change how it gets a reference to it, but just adding PresentationCore lets me reference the necessary assembly (without strings :) and then add it to the IronPython runtime.
The below code runs fine and prints out #646496C8
using System;
using IronPython.Hosting;
using Microsoft.Scripting.Hosting;
class Program
{
private static ScriptEngine _python;
private static readonly string _script = #"
from System.Windows.Media import Color
c = Color()
c.A = 100
c.B = 200
c.R = 100
c.G = 150
c
";
public static dynamic ExectureStatements(string expression)
{
var neededAssembly = typeof(System.Windows.Media.Color).Assembly;
_python.Runtime.LoadAssembly(neededAssembly);
ScriptScope scope = _python.CreateScope();
ScriptSource source = _python.CreateScriptSourceFromString(expression);
return source.Execute(scope);
}
static void Main(string[] args)
{
_python = Python.CreateEngine();
var output = ExectureStatements(_script);
Console.WriteLine(output);
}
}