I am writing a scripting language, i've done the lexer and parser and i want to dynamically execute in the memory.
Lets say i have something like
function Hello(World)
{
Print(world);
}
var world = "World";
var boolean = true;
if(boolean == true)
{
Print("True is True");
}
else
{
Print("False is True");
}
Hello(world);
what would be the best way to execute this snippet i'ved tried
1) OpCode Il Generation (i couldn't get if statement to work or anything other than Print function)
2) RunSharp, i cannot do the functions cause the way i can do it i have no idea how.
If anyone could point me to the right direction!
Alittle Code will help
Link to resource (not something like IronPython) would be also good
your script language like JavaScript,if it dynamic compile in memory.
example:
//csc sample.cs -r:Microsoft.JScript.dll
using System;
using System.CodeDom.Compiler;
using Microsoft.JScript;
class Sample {
static public void Main(){
string[] source = new string[] {
#"import System;
class JsProgram {
function Print(mes){
Console.WriteLine(mes);
}
function Hello(world){
Print(world);
}
function proc(){
var world = ""World"";
var bool = true;
if(bool == true){
Print(""True is True"");
}
else{
Print(""False is True"");
}
Hello(world);
}
}"
};
var compiler = new JScriptCodeProvider();
var opt = new CompilerParameters();
opt.ReferencedAssemblies.Add("System.dll");
opt.GenerateExecutable = false;
opt.GenerateInMemory = true;
var result = compiler.CompileAssemblyFromSource(opt, source);
if(result.Errors.Count > 0){
Console.WriteLine("Compile Error");
return;
}
var js = result.CompiledAssembly;
dynamic jsProg = js.CreateInstance("JsProgram");
jsProg.proc();
/*
True is True
World
*/
}
}
generate c# source and compile it :-)
http://support.microsoft.com/kb/304655
If I understand you right, you want to compile and run the code on runtime? then you could try http://www.csscript.net/index.html , its an example on the same page linked.
Related
Is there a way to enable "import <module>.js;" statements in an embedded V8 Runtime using Microsoft ClearScript?
I couldn't find any examples and makes me think I'd have to parse the script file myself first to enable this.
Yes there is. See answer to this question as the basic approach. That question was about enabling CommonJS Require. For ES6 modules approach you will want something like this:
using System;
using Microsoft.ClearScript;
using Microsoft.ClearScript.JavaScript;
using Microsoft.ClearScript.V8;
namespace ConsoleApp1
{
class Program
{
static void Main()
{
V8ScriptEngine engine = new V8ScriptEngine();
engine.DocumentSettings.SearchPath = #"c:\temp\js\";
engine.DocumentSettings.AccessFlags = DocumentAccessFlags.EnableFileLoading;
engine.AddHostType(typeof(Console));
Console.WriteLine("Hello from C#");
engine.Execute(new DocumentInfo() { Category = ModuleCategory.Standard }, #"
Console.WriteLine('Hello from Javascript');
import {print} from 'a.js';
import {add} from 'b.js';
print(add(30, 12));
Console.WriteLine('Javascript signing off...');
");
Console.ReadKey();
}
}
}
Where the JS looks like this:
// File c:\temp\js\a.js
export function print(txt) {
Console.WriteLine('The answer to Life etc is ... ' + txt);
}
// File c:\temp\js\b.js
export function add(var1, var2) {
return var1 + var2;
}
Result is:
This example is reading files from the local file system as indicated by the AccessFlags = EnableFileLoading setting, with the SearchPath setting giving the path, or paths if given a comma-separated list of paths.
It is the 'ModuleCategory.Standard' option that enables ES6-stylee module loading.
You could also use a roll-your-own require() function similar to node.js. I wrote a blog article here and there's a working CodePen to illustrate the approach which was inspired by an article by Michele Nasti which was itself based on the ideas in chapter 10 of the book Eloquent JavaScript by Marijn Haverbeke.
Here is my coded example:
const myCode1 = `
let utils = function (){
this.say = function(x){
log('utils: says = ' + x)
};
return this;
}
exports.utils = utils;
`;
const myCode2 = `
let customer = function (){
this.say = function(x){
log('Customer: says = ' + x)
};
return this;
}
exports.customer = customer;
`;
/*
*/
// I am loading simple source code strings into an array - in the real solution
// you would use some kind of source code fetch / load to string process.
let sourceCode = {c1: myCode1, c2: myCode2};
myRequire.cache = Object.create(null);
function myRequire(name) {
log(`myRequire: You require file ${name}`)
if (!(name in myRequire.cache)) {
log(`myRequire: ${name} is not in cache; reading from disk`)
let code = sourceCode[name]; // load the code - this is bespoke to your env
let module = {exports: {}};
myRequire.cache[name] = module;
let wrapper = Function("require, exports, module", code);
wrapper(myRequire, module.exports, module);
}
log(`myRequire: ${name} is in cache. Returning it...`)
return myRequire.cache[name].exports;
}
// myRequire() produces an object from the 'exports' object in the loaded code.
//let myExports = new myRequire('c1');
// we can then refer to these as
// let util = myExports.utils();
// or just use
// let util = new myRequire('c1').utils();
// So...Require c1 will create an object with exports.
let util = new myRequire('c1').utils();
util.say('I am alive!')
log("");
// Require c2 will create an object with exports.
let cust = new myRequire('c2').customer();
cust.say('I am alive too!')
function log(msg){
$('#log').html($('#log').html() + "<br />" + msg);
}
The output is
myRequire: You require file c1
myRequire: c1 is not in cache; reading from disk
myRequire: c1 is in cache. Returning it...
utils: says = I am alive!
myRequire: You require file c2
myRequire: c2 is not in cache; reading from disk
myRequire: c2 is in cache. Returning it...
Customer: says = I am alive too!
I want to call a python function from C# code. To do that, I used Python for .NET to call function as shown in the following lines of code
using System;
using Python.Runtime;
public class Test{
public static void Main(){
using(Py.GIL()){
dynamic lb = Py.Import("lb");
dynamic result = lb.analyze("SomeValue");
Console.WriteLine(result);
}
}
}
The python function is something like this:
def analyze(source, printout = False, raw = True):
# removed for bravity
So the question is, how can I set "raw" to False when I call the analyze function from C# code. I tried the following but it didn't work.
1. dynamic result = lb.analyze("SomeSource", raw : false); // No result
2. dynamic result = lb.analyze("SomeSource", #"raw = False"); // No result
I know it is easy to do by doing this:
dynamic result = lb.analyze("SomeSource", False, False);
But what if there is more than six or seven named parameter, it would not be great to insert it all manually and change the one I wanted. For example, the python library that I am using have 12 named parameter with default value including two more parameters with no default value.
UPDATED
I also tried:
3. dynamic result = lb.analyze("SomeSource", raw = false); // C# compilation error
To apply keyword arguments use:
lb.analyze("SomeSource", Py.kw("raw", false));
See readme.
Another approach is using C# keyword argument syntax that was recently added to pythonnet:
lb.analyze("SomeSource", raw: false);
Since I am using one function to call python scripts I have used a Listto hold the parameter values. I am also passing in a class name and function name since my python scripts contain multiple classes with multiple functions. I don't use the 'self' parameter in any of my classes, so they are static functions. I am providing a snippet of my code to help you and anyone else out that is using python in .net. I personally use it for communciation with USB.
Here is an example of one of my callers. Ignore the function name but look at how it's calls the ExecuteScript and passing int he parameterset. Notice the list is of type object, incase your paramters are a mix of string/int/bool/objects etc.
public string SendCommand(string comport, string command)
{
try
{
List<object> parameterSet = new() { comport, command };
string result = _pythonService.ExecuteScript<string>("usb", "usb", "sendCommand", parameterSet);
return result;
}
catch (Exception)
{
throw;
}
}
Here is a function that executes the class function
public dynamic? ExecuteScript<T>(string scriptFile, string className, string functionName, List<object> paramset)
{
T? result = default;
try
{
// Location of all the python scripts in the project. lets get the python file we are specifying in the function param
string file = $"{Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location)}\\PythonScripts\\{scriptFile}.py";
// This is initalized in the program.cs, but just want to make sure it's initialized in case something happens
if (!PythonEngine.IsInitialized)
{
PythonEngine.Initialize();
Py.GIL();
}
using (var scope = Py.CreateScope())
{
PyObject? pythonReturn; // Our returned PythonObject from the python function call
string code = File.ReadAllText(file); // Get the python file as raw text
var scriptCompiled = PythonEngine.Compile(code, file); // Compile the code/file
scope.Execute(scriptCompiled); // Execute the compiled python so we can start calling it.
PyObject pythonClass = scope.Get(className); // Lets get an instance of the class in python
// Add parameters to the function?
if (paramset != null && paramset.Count > 0)
{
PyObject[] pyParams = new PyObject[paramset.Count]; // This is an array of python parameters passed into a function
// Loop through our incoming c# list of parameters and create PythonObject array .
for (int i = 0; i < paramset.Count; i++)
{
pyParams[i] = paramset[i].ToPython();
}
pythonReturn = pythonClass.InvokeMethod(functionName, pyParams); // Call the function on the class with parameters
}
else // We aren't using parameters here
pythonReturn = pythonClass.InvokeMethod(functionName); // Call the function on the class
// Lets convert our returned pythonObject to that of the object type (C#)
object? netObject = pythonReturn.AsManagedObject(typeof(object));
// A special case of when we want a list back. We will convert the object to the specific type in the caller function
if (typeof(T) == typeof(IList<object>))
{
object[] something = pythonReturn.As<object[]>();
return something;
}
// Convert the c# object to that of what we expect to be returned,. string/int/bool/class
if (netObject != null)
result = (T)netObject; // convert the returned string to managed string object
}
return result;
}
catch (Exception)
{
// Handle your exceptions here
throw;
}
}
If you don't care about the entire function and just want the quick snippet of adding the params:
// Add parameters to the function?
if (paramset != null && paramset.Count > 0)
{
PyObject[] pyParams = new PyObject[paramset.Count]; // This is an array of python parameters passed into a function
// Loop through our incoming c# list of parameters and create PythonObject array .
for (int i = 0; i < paramset.Count; i++)
{
pyParams[i] = paramset[i].ToPython();
}
pythonReturn = pythonClass.InvokeMethod(functionName, pyParams); // Call the function on the class with parameters
}
else // We aren't using parameters here
pythonReturn = pythonClass.InvokeMethod(functionName); // Call the function on the class
I work in a research group and I've been tasked with adding in scripting functionality to a data acquisition program. Ideally, I want to have the ability to write scripts while the data acquisition software is running (and save those scripts as files on the go). A command line might also be nice.
I'm not very experienced at all with C#, but I do have quite a bit of coding experience in other language (Objective-C, Python). I saw this link https://blogs.msdn.microsoft.com/cdndevs/2015/12/01/adding-c-scripting-to-your-development-arsenal-part-1/ which details the "Roselyn Scripting Package" but I'm not sure if that's my best option.
Can anybody suggest the easiest way of getting full scripting functionality? (I'm trying to avoid losing months of my life here =p). Links to start at/advice is much appreciated.
Thanks!
You posted an interesting link for me because I just prototyped something like that some weeks ago, but have not implemented yet. My goal is to create a C# "immediate" console on a webpage.
Have some minor issues regarding loading some assemblies programatically and have to reference them explicitly.
Here is the code behind, please later post your solution, I would be interested to know.
This alows to write c# code at runtime and also get a String return.
protected void getImmediateResult_Click(object sender, EventArgs e)
{
//building the code
string source = #"using System;
class MyType{
public static String Evaluate(){
<!expression!>
}}";
string expression = this.txtimmediate.Text;
string finalSource = source.Replace("<!expression!>", expression);
textcodeCheck.Text = finalSource;
var compileUnit = new CodeSnippetCompileUnit(finalSource);
//preparing compilation
CodeDomProvider provider = new Microsoft.CSharp.CSharpCodeProvider();
// Create the optional compiler parameters
//this correctly references the application but no System.Web etc
string[] refArray = new string[2];
UriBuilder uri = new UriBuilder(Assembly.GetExecutingAssembly().CodeBase);
refArray[0] = uri.Path;
//this works
refArray[1] = "System.Web" + ".dll";
////NOT WORKING for non microsoft assemblies
//var allRefs = Assembly.GetExecutingAssembly().GetReferencedAssemblies();
//string[] refArray = new string[allRefs.Length + 1];
//int i = 1;
//foreach (AssemblyName refer in allRefs)
//{
// refArray[i] = refer.Name + ".dll";
// i++;
//}
var compilerParameters = new CompilerParameters(refArray);
CompilerResults compilerResults = provider.CompileAssemblyFromDom(compilerParameters, compileUnit);
if (compilerResults.Errors.Count > 0)
{
//1st error
this.txtResult.Text = compilerResults.Errors[0].ErrorText;
return;
}
//running it
Type type = compilerResults.CompiledAssembly.GetType("MyType");
MethodInfo method = type.GetMethod("Evaluate");
String result = (String)method.Invoke(null, null);
this.txtResult.Text = result;
}
If you're willing to use IronPython, you can execute scripts directly in C#:
using IronPython.Hosting;
using Microsoft.Scripting.Hosting;
private static void doPython()
{
ScriptEngine engine = Python.CreateEngine();
engine.ExecuteFile(#"test.py");
}
Get IronPython here.
We try to figure out how to generate code with Roslyn. I'm not speaking about something like CSharpSyntaxTree.ParseText that will take some strings and convert them into an AST. Instead, I would like to build my model somehow like this (pseudo code):
Create file as compilation unit
Add class MyClass to file
Add method DoSomething to MyClass
Set body of DoSomething in a similar fashion like System.Linq.Expressions
We recently discovered Microsoft.CodeAnalysis.CSharp.SyntaxFactory, and it seemed to be promising. However, obviously we have to add trivia ourselves.
After building a tree with SyntaxFactory.CompilationUnit() and adding some members back and forth, the output of ToFullString() is just a bunch of text, that is neither readable, nor compilable (e.g., missing braces). Do we miss something when generating the text from the model?
EDIT:
When using workspaces, you can set options affecting the whitespace behavior:
public string Generate (CompilationNode rootNode)
{
var cw = new CustomWorkspace();
cw.Options.WithChangedOption (CSharpFormattingOptions.IndentBraces, true);
var formattedCode = Formatter.Format (CreateFile(rootNode), cw);
return formattedCode.ToFullString();
}
This already yields a better result. Can someone confirm this as a good solution or is it rather a hack?
One problem remains. We want to generate an auto-property, currently using SF.AccessorDeclaration but it misses the semicolon when converting to the full string.
You basically have to add block definitions, then Roslyn handles the trivia for you as long as you use the Formatter (as you have written)
Here is an example for a simple class that is generated correctly without myself having to specify any trivia
var consoleWriteLine = Syntax.MemberAccessExpression(
SyntaxKind.SimpleMemberAccessExpression,
Syntax.IdentifierName("Console"),
name: Syntax.IdentifierName("WriteLine"));
var arguments = Syntax.ArgumentList (
Syntax.SeparatedList (
new[]
{
Syntax.Argument (
Syntax.LiteralExpression (
SyntaxKind.StringLiteralExpression,
Syntax.Literal (#"""Goodbye everyone!""", "Goodbye everyone!")))
}));
var consoleWriteLineStatement = Syntax.ExpressionStatement (Syntax.InvocationExpression (consoleWriteLine, arguments));
var voidType = Syntax.ParseTypeName ("void");
var method = Syntax.MethodDeclaration (voidType, "Method").WithBody (Syntax.Block(consoleWriteLineStatement));
var intType = Syntax.ParseTypeName ("int");
var getterBody = Syntax.ReturnStatement (Syntax.DefaultExpression (intType));
var getter = Syntax.AccessorDeclaration (SyntaxKind.GetAccessorDeclaration, Syntax.Block (getterBody));
var property = Syntax.PropertyDeclaration (intType, "Property").WithAccessorList (Syntax.AccessorList (Syntax.SingletonList (getter)));
var #class = Syntax.ClassDeclaration ("MyClass").WithMembers (Syntax.List (new MemberDeclarationSyntax[] { method, property }));
var cw = new CustomWorkspace();
cw.Options.WithChangedOption (CSharpFormattingOptions.IndentBraces, true);
var formattedCode = Formatter.Format (#class, cw);
Console.WriteLine (formattedCode.ToFullString());
Note: Syntax = Microsoft.CodeAnalysis.CSharp.SyntaxFactory
This generates the following class definiton:
class MyClass
{
void Method()
{
Console.WriteLine("Goodbye everyone!");
}
int Property
{
get
{
return default(int);
}
}
}
Seems fine.
I had this same problem and found CustomWorkspace is now called AdhocWorkspace.
var cw = new AdhocWorkspace();
cw.Options.WithChangedOption(CSharpFormattingOptions.IndentBraces, true);
var formatter = Formatter.Format(cu, cw);
StringBuilder sb = new StringBuilder();
using (StringWriter writer = new StringWriter(sb))
{
formatter.WriteTo(writer);
}
var code = sb.ToString();
On my form I have a button click
private void button1_Click(object sender, EventArgs e)
{
do something
}
How on the click would I load my do something from a text file, for example my text file looks like this:
MessageBox.Show("hello");
label1.Text = "Hello";
on click it does everything in my text file, if possible.
Here is a very simple example, just to prove this is possible. Basically, you use CodeDomProvider to compile source at runtime, then execute using reflection.
var provider = CodeDomProvider.CreateProvider("C#");
string src=#"
namespace x
{
using System;
public class y
{
public void z()
{
Console.WriteLine(""hello world"");
}
}
}
";
var result = provider.CompileAssemblyFromSource(new CompilerParameters(), src);
if (result.Errors.Count == 0)
{
var type = result.CompiledAssembly.GetType("x.y");
var instance = Activator.CreateInstance(type);
type.GetMethod("z").Invoke(instance, null);
}
Edit
As #Agat points out, the OP seems to require a sort of scripting framework (it makes use of label1, a property of the current object), whereas my answer above obviously does not provide that. The best I can think of is a limited solution, which would be to require dependencies to be specified explicitly as parameters in the "script". Eg, write the scripted code like this:
string src = #"
namespace x
{
using System.Windows;
public class y
{
public void z(Label label1)
{
MessageBox.Show(""hello"");
label1.Text = ""Hello"";
}
}
}
";
Now you can have the caller examine the parameters, and pass them in from the current context, again using reflection:
var result = provider.CompileAssemblyFromSource(new CompilerParameters(), src);
if (result.Errors.Count == 0)
{
var type = result.CompiledAssembly.GetType("x.y");
var instance = Activator.CreateInstance(type);
var method = type.GetMethod("z");
var args = new List<object>();
// assume any parameters are properties/fields of the current object
foreach (var p in method.GetParameters())
{
var prop = this.GetType().GetProperty(p.Name);
var field = this.GetType().GetField(p.Name);
if (prop != null)
args.Add(prop.GetValue(this, null));
else if (field != null);
args.Add(field.GetValue(this));
else
throw new InvalidOperationException("Parameter " + p.Name + " is not found");
}
method.Invoke(instance, args.ToArray());
}
Like the other answers have stated, it isn't an easy thing to implement and can possibly be done through reflection depending on how advanced your scripts are.
But no one #BrankoDimitrijevic mentioned Roslyn and it is a great tool. http://msdn.microsoft.com/en-us/vstudio/roslyn.aspx
It hasn't been updated in quite awhile (Sept.2012) and doesn't have all of the features of C# implemented, however, it did have a lot of it implemented when I played around with this release.
By adding your assembly as a reference to the scripting session, you're able to gain access to all of your assembly's types and script against them. It also supports return values so you can return any data that a scripted method generates.
You can find what isn't implemented here.
Below is a quick and dirty example of Roslyn that I just wrote and tested. Should work right out of box after installing Roslyn from NuGet. The small bloat at the initialization of the script engine can easily be wrapped up in a helper class or method.
The key is passing in a HostObject. It can be anything. Once you do, your script will have full access to the properties. Notice that you just call the properties and not the host object in the script.
Basically, your host object will contain properties of the data you need for your script. Don't necessarily think of your host object as just a single data object, but rather a configuration.
public class MyHostObject
{
public string Value1 { get; set; }
public string Value2 { get; set; }
}
public class RoslynTest
{
public void Test()
{
var myHostObject = new MyHostObject
{
Value1 = "Testing Value 1",
Value2 = "This is Value 2"
};
var engine = new ScriptEngine();
var session = engine.CreateSession(myHostObject);
session.AddReference(myHostObject.GetType().Assembly.Location);
session.AddReference("System");
session.AddReference("System.Core");
session.ImportNamespace("System");
// "Execute" our method so we can call it.
session.Execute("public string UpdateHostObject() { Value1 = \"V1\"; Value2 = \"V2\"; return Value1 + Value2;}");
var s = session.Execute<string>("UpdateHostObject()");
//s will return "V1V2" and your instance of myHostObject was also changed.
}
}
No. You can not.
At least in any simple way.
The thing you want is something like eval('do something') from javascript.
That's not possible to do with C#. C# is a language which needs compilation before execution unlike javascript (for instance).
The only way to implement that is to build your own (pretty complicated as for beginner) parser and execute it in such way.
UPDATED:
Actually, as JDB fairly noticed, that's really not the only way. I love programming! There are so many ways to make a freakky (or even sometimes that really can be necessary for some custom interesting tasks (or even learning)!) code. he he
Another approach I've got in my mind is building some .cs file, then compiling it on-the-fly and working with it as some assembly or some other module. Right.