How can I retrieve a nested type with its fully qualified name?

Question

I cannot seem to retrieve a nested class using Roslyn's Compilation.GetTypeByMetaDataName() method.

For example:

var tree = CSharpSyntaxTree.ParseText(@"
using System;
namespace MyNamespace
{
    public class MyClass 
    {
        public class MyInnerClass
        {
        }
    }
}
");

var Mscorlib = new MetadataFileReference(typeof(object).Assembly.Location);
var compilation = CSharpCompilation.Create("MyCompilation",
    syntaxTrees: new[] { tree }, references: new[] { Mscorlib });

//Correctly retrieves outer type.
var outerClass = compilation.GetTypeByMetadataName("MyNamespace.MyClass");
//Cannot correctly retrieve inner type (returns null)
var innerClass = compilation.GetTypeByMetadataName("MyNamespace.MyClass.MyInnerClass");

Is it possible to retrieve nested types using their fully qualified names?

I realize one work around would be to first check if the containing type contained any types using INamespaceorTypeSymbol.GetTypeMembers() , but I would much rather not go down that path. I'd assume the GetTypeByMetaDataName() method should work for any type, nested or otherwise.

Answer 1

Try using + to separate inner classes:

var innerClass = compilation.GetTypeByMetadataName("MyNamespace.MyClass+MyInnerClass");

The documentation for the Type.GetType method discusses the syntax used for naming nested types.