当前上下文中不存在名称'xxx'(是否缺少对程序集的引用)

Question

我已经安装了Microsoft.CodeAnalysis.CSharp&.Net Core 2.2控制台应用程序中的Microsoft.CodeAnalysis.CSharp.Scripting(3.3.1版(包，我还开发了以下代码：

SyntaxTree syntaxTree = CSharpSyntaxTree.ParseText(@"
public class MyGlobals
{
public int Age {get; set;} = 21;
}
");
var references = new List<MetadataReference>
{
MetadataReference.CreateFromFile(typeof(object).Assembly.Location)
};
var compilation = CSharpCompilation.Create("DynamicAssembly")
.WithOptions(new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary))
.AddSyntaxTrees(syntaxTree)
.AddReferences(references);
Type globalsType = null;
Assembly assembly = null;
using (var memoryStream = new MemoryStream())
{
var compileResult = compilation.Emit(memoryStream);
assembly = Assembly.Load(memoryStream.GetBuffer());
if (compileResult.Success)
{
globalsType = assembly.GetType("MyGlobals");
}
}
var globals = Activator.CreateInstance(globalsType);
var validationResult = CSharpScript.EvaluateAsync<bool>("Age == 21", globals: globals);

创建了globals对象，但未计算表达式，CSharpScript抛出以下异常：

名称"Age"在当前上下文中不存在(是否缺少对程序集"DynamicAssembly，Version=0.0.0.0，Culture=neutral，PublicKeyToken=null"的引用？(">

是否有我错过的设置？

Answer 1

出现错误的原因是没有引用刚刚创建的DynamicAssembly。要解决此问题，可以将ScriptOptions传递给CSharpScript.EvaluateAsync<bool>()调用。以下代码对我来说运行得很好。

SyntaxTree syntaxTree = CSharpSyntaxTree.ParseText(@"
public class MyGlobals
{
public int Age {get; set;} = 21;
}
");
var references = new List<MetadataReference>
{
MetadataReference.CreateFromFile(typeof(object).Assembly.Location)
};
var compilation = CSharpCompilation.Create("DynamicAssembly")
.WithOptions(new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary))
.AddSyntaxTrees(syntaxTree)
.AddReferences(references);
Type globalsType = null;
Assembly assembly = null;
using (var memoryStream = new MemoryStream())
{
var compileResult = compilation.Emit(memoryStream);
var buffer = memoryStream.GetBuffer();
File.WriteAllBytes("DynamicAssembly.dll", buffer);
assembly = Assembly.LoadFile(Path.GetFullPath("DynamicAssembly.dll"));
if (compileResult.Success)
{
globalsType = assembly.GetType("MyGlobals");
}
}
var globals = Activator.CreateInstance(globalsType);
var options = ScriptOptions.Default.WithReferences("DynamicAssembly.dll");
var validationResult = CSharpScript.EvaluateAsync<bool>(
"Age == 21",
globals: globals,
options: options
);
Console.WriteLine(await validationResult);