c# - AsOrdered() 不工作

Question

我正在尝试将 AsParallell() 与 AsOrdered() 方法一起使用，但我总是看到无序的结果。

using System;
using System.Linq;
using System.Collections.Generic;

namespace Parallel
{
    class MainClass
    {
        public static void Main(string[] args)
        {
            List<String> cities = new List<String>() {
                "Barcelona",
                "Valencia",
                "Sevilla",
                "Zaragoza",
                "Málaga",
                "Murcia",
                "Palma",
                "Las Palmas de Gran Canaria",
                "Alicante",
                "Madrid",
                "Córdoba",
                "Valladolid",
                "Tarrasa",
                "Vigo",
                "Gijón",
                "Cartagena",
                "Hospitalet de Llobregat",
                "Vitoria",
                "La Coruña",
                "Granada",
                "Elche",
                "Oviedo",
                "Badalona"
            };

            var filtered = cities.AsParallel().AsOrdered().Where(c => c.ToUpper().StartsWith("B") || c.ToUpper().EndsWith("A")).ToArray();

            Console.WriteLine("Cities starting with \"B\" or ends with \"A\"");

            foreach (String city in filtered) 
            {
                Console.WriteLine(city);
            }

        }
    }
}

输出是:

Cities starting with "B" or ends with "A"BarcelonaValenciaSevillaZaragozaMálagaMurciaPalmaLas Palmas de Gran CanariaCórdobaTarrasaCartagenaVitoriaLa CoruñaGranadaBadalonaPress any key to continue...

怎么了？

我在 Mac 中使用 Visual Studio，Net Core 项目。

谢谢

Answer 1

AsOrdered()只维护 List<string> 中项目的原始顺序.如果您想按字母顺序排列项目，您可以使用 OrderBy方法:

var filtered = cities.AsParallel().Where(c => c.ToUpper().StartsWith("B") || c.ToUpper().EndsWith("A")).OrderBy(x => x).ToArray();