How to access a compiled assembly from CSharpCodeProvider without recompiling

Question

I have Microsoft.CSharp.CSharpCodeProvider CompileAssemblyFromSource working. Its definitely creating and returning what i need.

I know the compiled code ends up in the assembly, and cann ont be removed until the app domain is dispossed of.

How do you reuse the compiled called, without having to call the CompileAssemblyFromSource(myParams, myScript) everytime?

If i set myParams.OutputAssembly = 'MyAssembly"; I cannot seem to to instantiate an instance of it.

If the code is in memory, how can i check to see if it is there and how can i reload it without calling CompileAssemblyFromSource()?

Answer 1

Found a possible solution. At least working in my test app. When not using the OutputAssembly setting, .NET will create the assembly with a random name.

I got the name from the returned code object. objectReturned.GetType().Module.ScopeName.

Saving that name, so when i come back, if the script has not changed, i can just use the last compiled version.

Just remeber, everytime you compile, it will create a new entry in the assembly. Which can be seen in the AppDomain.CurrentDomain.GetAssemblies().

/// <summary>
/// 
/// </summary>
/// <param name="scriptString">My string i want to compile</param>
/// <param name="lastCompiledName">The random name .NET gave to my last in MEMORY compile
/// objectReturned.GetType().Module.ScopeName.Replace(".dll", "") to get the name.</param>
/// <param name="doForceCompile">If i want to override the one in MEMORY</param>
/// <param name="errors"></param>
/// <returns></returns>
public IScriptBuilder CompileCodeDomCSharp(String scriptString, string lastCompiledName, bool doForceCompile, out List<string> errors)
{

    var providerOptions = new Dictionary<string, string>();
    providerOptions.Add("CompilerVersion", "v4.0");
    var provider = new Microsoft.CSharp.CSharpCodeProvider(providerOptions);


    var cp = new CompilerParameters(new[] { "System.Core.dll" }) {
        GenerateExecutable = false,
        GenerateInMemory = true,
        TreatWarningsAsErrors = false,
        WarningLevel = 3,
        CompilerOptions = "/optimize",
        IncludeDebugInformation = false
    };
    cp.ReferencedAssemblies.Add(typeof(IScriptBuilder).Assembly.Location);
    // will write file to  C:\newprojects\NewPayroll\Utilities\CSharpScriptingTest\CSharpScriptWriter\CSharpScriptWriter\bin\Debug  -- causes issues for me.
    // cp.OutputAssembly = "MyScriptRunner";        

    errors = new List<string>();

    try
    {

        var assemblies = AppDomain.CurrentDomain.GetAssemblies();
        Type type;

        // use actual name if OutputAssembly is set
        // if (doForceCompile || x.All(a => a.FullName != "MyScriptRunner, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null"))   
        if (doForceCompile || assemblies.All(a => a.FullName != lastCompiledName + ", Version=0.0.0.0, Culture=neutral, PublicKeyToken=null"))
        {
            var results = provider.CompileAssemblyFromSource(cp, scriptString);
            type = results.CompiledAssembly.GetType("MyScriptRunner");
        }
        else
        {
            // use actual name if OutputAssembly is set
            // var myScriptRunner = x.FirstOrDefault(a => a.FullName == "MyScriptRunner, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null");   
            var myScriptRunner = assemblies.FirstOrDefault(a => a.FullName == lastCompiledName + ", Version=0.0.0.0, Culture=neutral, PublicKeyToken=null");
            var myScriptRunnerObject = myScriptRunner.CreateObject("*");
            type = myScriptRunnerObject.GetType();
        }


        dynamic obj = Activator.CreateInstance(type);

        return (IScriptBuilder)obj;

    }
    catch (Exception ex)
    {
        // Not returning or handling error an my test app.
        return null;
    }

}