using Microsoft.CSharp;
using System.CodeDom.Compiler;
using System.Reflection;
using System.Text; namespace System
{
public static class CompileCSCAtRuntime
{
public static void HelloWorld()
{
string code = @"
using System; namespace First
{
public class Program
{
public static void Main()
{
" +
"Console.WriteLine(\"Hello, world!\");"
+ @"
}
}
}
"; CSharpCodeProvider provider = new CSharpCodeProvider();
CompilerParameters parameters = new CompilerParameters(); // Reference to System.Drawing library
parameters.ReferencedAssemblies.Add("System.Drawing.dll");
// True - memory generation, false - external file generation
parameters.GenerateInMemory = true;
// True - exe file generation, false - dll file generation
parameters.GenerateExecutable = true; CompilerResults results = provider.CompileAssemblyFromSource(parameters, code); if (results.Errors.HasErrors)
{
StringBuilder sb = new StringBuilder(); foreach (CompilerError error in results.Errors)
{
sb.AppendLine(String.Format("Error ({0}): {1}", error.ErrorNumber, error.ErrorText));
} throw new InvalidOperationException(sb.ToString());
} Assembly assembly = results.CompiledAssembly;
Type program = assembly.GetType("First.Program");
MethodInfo main = program.GetMethod("Main"); main.Invoke(null, null);
} public static void TestMeothds()
{
MethodInfo function = CreateFunction("x + 2 * y");
var betterFunction = (Func<double, double, double>)Delegate.CreateDelegate(typeof(Func<double, double, double>), function);
Func<double, double, double> lambda = (x, y) => x + 2 * y; DateTime start;
DateTime stop;
double result;
int repetitions = 5000000; start = DateTime.Now;
for (int i = 0; i < repetitions; i++)
{
result = OriginalFunction(2, 3);
}
stop = DateTime.Now;
Console.WriteLine("Original - time: {0} ms", (stop - start).TotalMilliseconds); start = DateTime.Now;
for (int i = 0; i < repetitions; i++)
{
result = (double)function.Invoke(null, new object[] { 2, 3 });
}
stop = DateTime.Now;
Console.WriteLine("Reflection - time: {0} ms", (stop - start).TotalMilliseconds); start = DateTime.Now;
for (int i = 0; i < repetitions; i++)
{
result = betterFunction(2, 3);
}
stop = DateTime.Now;
Console.WriteLine("Delegate - time: {0} ms", (stop - start).TotalMilliseconds); start = DateTime.Now;
for (int i = 0; i < repetitions; i++)
{
result = lambda(2, 3);
}
stop = DateTime.Now;
Console.WriteLine("Lambda - time: {0} ms", (stop - start).TotalMilliseconds);
} public static double OriginalFunction(double x, double y)
{
return x + 2 * y;
} public static MethodInfo CreateFunction(string function)
{
string code = @"
using System; namespace UserFunctions
{
public class BinaryFunction
{
public static double Function(double x, double y)
{
return func_xy;
}
}
}
"; string finalCode = code.Replace("func_xy", function); CSharpCodeProvider provider = new CSharpCodeProvider();
CompilerResults results = provider.CompileAssemblyFromSource(new CompilerParameters(), finalCode); Type binaryFunction = results.CompiledAssembly.GetType("UserFunctions.BinaryFunction");
return binaryFunction.GetMethod("Function");
}
}
}