如何在Roslyn中没有源代码的情况下浏览程序集的内容

Question

Roslyn allows you to get the CSharpCompilation from the source code:

// Getting the AST node
 var tree = (CSharpSyntaxTree)CSharpSyntaxTree.ParseText("my code");

// Loading the semantic model
CSharpCompilation compilation = CSharpCompilation.Create("Compilation", new[] { tree });

Then I get the SemanticModel :

var sm = compilation.GetSemanticModel(tree);

The I usually try to get symbols like this:

sm.GetSymbolInfo(node);

No source code

What if I have no source code?

• How can I get a CSharpCompilation without having the source code but just the DLL?
• How can I enumerate all symbols in the DLL and retrieve all the information about those types?

Is Roslyn capable of this?

Answer 1

Roslyn is not meant for reading assemblies, reflection libraries like System.Reflection, Mono.Cecil, System.Reflection.Metadata or IKVM.Reflection are likely going to be better suited for that.

That being said, if you really want to do it, you can get a symbol for an assembly by creating a dummy compilation that references the assembly and then using GetAssemblyOrModuleSymbol . For example, to write all types in an assembly to the console, you can use code like this:

var reference = MetadataReference.CreateFromFile(dllPath);
var compilation = CSharpCompilation.Create(null).AddReferences(reference);

var assemblySymbol = (IAssemblySymbol)compilation.GetAssemblyOrModuleSymbol(reference);

Write(assemblySymbol.GlobalNamespace);

void Write(INamespaceOrTypeSymbol symbol)
{
    if (symbol is ITypeSymbol)
        Console.WriteLine(symbol);

    foreach (var memberSymbol in symbol.GetMembers().OfType<INamespaceOrTypeSymbol>())
    {
        Write(memberSymbol);
    }
}

Answer 2

Roslyn is a compiler. It takes source code and produces assemblies.

To inspect assemblies, you need to use reflection .

Answer 3

The tool NDepend offers a code model that can be built from assemblies only . No PDB nor source code is required, yet more info can be provided if PDB and source code are available. More explanation on NDepend analysis inputs here .

The code model can then be explored through C# LINQ queries . Around 150 predefined code rules are written with such predefined LINQ query.

The code model built proposes many facilities : code metrics, dependencies, diff since a baseline, state mutability, technical-debt estimation...

Disclaimer: I work for NDepend