使用LINQ组合两个表达式？

using System;
using System.Linq.Expressions;

class Program
{
    static void Main()
    {
        // 定义两个表达式
        Expression<Func<int, int>> expr1 = x => x * 2;
        Expression<Func<int, int>> expr2 = y => y + 1;

        // 使用LINQ的Compose方法组合两个表达式
        var combinedExpr = expr1.Compose(expr2);

        // 输出组合后的表达式结果
        Console.WriteLine(combinedExpr.Compile()(2));  // 输出：5
    }
}

public static class ExpressionExtensions
{
    // 定义Compose方法，用于组合两个表达式
    public static Expression<Func<T, TResult>> Compose<T, TIntermediate, TResult>(
        this Expression<Func<T, TIntermediate>> expr1,
        Expression<Func<TIntermediate, TResult>> expr2)
    {
        var parameter = Expression.Parameter(typeof(T));
        var intermediate = expr1.Body.Replace(expr1.Parameters[0], parameter);
        var body = expr2.Body.Replace(expr2.Parameters[0], intermediate);
        return Expression.Lambda<Func<T, TResult>>(body, parameter);
    }

    // 定义Replace方法，用于替换表达式中的参数
    public static Expression Replace(this Expression expression, Expression searchEx, Expression replaceEx)
    {
        return new ReplaceVisitor(searchEx, replaceEx).Visit(expression);
    }

    // 替换访问器类
    private class ReplaceVisitor : ExpressionVisitor
    {
        private readonly Expression _searchEx;
        private readonly Expression _replaceEx;

        public ReplaceVisitor(Expression searchEx, Expression replaceEx)
        {
            _searchEx = searchEx;
            _replaceEx = replaceEx;
        }

        public override Expression Visit(Expression node)
        {
            return node == _searchEx ? _replaceEx : base.Visit(node);
        }
    }
}