Roslyn:声明变量，然后列出它们

using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.Syntax;
using System;

class Program
{
    static void Main()
    {
        // 创建变量声明节点
        VariableDeclarationSyntax variableDeclaration = SyntaxFactory.VariableDeclaration(
            SyntaxFactory.ParseTypeName("int"),
            SyntaxFactory.SeparatedList(new[] {
                SyntaxFactory.VariableDeclarator("x"),
                SyntaxFactory.VariableDeclarator("y")
            })
        );

        // 创建语法树
        SyntaxTree syntaxTree = SyntaxFactory.SyntaxTree(
            SyntaxFactory.CompilationUnit().AddMembers(
                SyntaxFactory.NamespaceDeclaration(SyntaxFactory.IdentifierName("MyNamespace"))
                    .AddMembers(
                        SyntaxFactory.ClassDeclaration("MyClass")
                            .AddMembers(
                                SyntaxFactory.MethodDeclaration(SyntaxFactory.ParseTypeName("void"), "MyMethod")
                                    .AddBodyStatements(
                                        SyntaxFactory.LocalDeclarationStatement(variableDeclaration)
                                    )
                            )
                    )
            )
        );

        // 获取语法树的根节点
        SyntaxNode root = syntaxTree.GetRoot();

        // 打印语法树
        Console.WriteLine(root.ToString());
    }
}