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0.0.1-alpha

PSRunspacedDelegate/RunspacedDelegateFactory.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Management.Automation.Runspaces;
 
namespace PowerShell
{
    public class RunspacedDelegateFactory
    {
        public static Delegate NewRunspacedDelegate(Delegate _delegate, Runspace runspace)
        {
            Action setRunspace = () => Runspace.DefaultRunspace = runspace;
 
            return ConcatActionToDelegate(setRunspace, _delegate);
        }
 
        private static Expression ExpressionInvoke(Delegate _delegate, params Expression[] arguments)
        {
            var invokeMethod = _delegate.GetType().GetMethod("Invoke");
 
            return Expression.Call(Expression.Constant(_delegate), invokeMethod, arguments);
        }
 
        public static Delegate ConcatActionToDelegate(Action a, Delegate d)
        {
            var parameters =
                d.GetType().GetMethod("Invoke").GetParameters()
                .Select(p => Expression.Parameter(p.ParameterType, p.Name))
                .ToArray();
 
            Expression body = Expression.Block(ExpressionInvoke(a), ExpressionInvoke(d, parameters));
 
            var lambda = Expression.Lambda(d.GetType(), body, parameters);
 
            var compiled = lambda.Compile();
             
            return compiled;
        }
    }
}