Question

我正在使用C＃阅读.txt文件，该文件包含单词列表，我需要按字母顺序对列表进行排序

static void Main(string[] args)
{
    StreamReader objReader = new StreamReader(
        @"C:\Users\thoma\Documents\Visual Studio 2019\Backup Files\data.txt");

    string orden = "";
    ArrayList arrText = new ArrayList();

    while (orden != null)
    {
        orden = objReader.ReadLine();
        if (orden != null) arrText.Add(orden);
    }
    objReader.Close();

    foreach (string sOutput in arrText)
        Console.WriteLine(sOutput);

    Console.WriteLine("Order alphabetically descendant press 'a': ");
    Console.WriteLine("Ordener ascending alphabetical press 'b': ");

    orden = Console.ReadLine();

    switch (orden)
    {
        case "a":
             string ordenado = new String(orden.OrderBy(x => x).ToArray());
            Console.WriteLine(ordenado);
            break;
        case "b":
            Console.WriteLine("");
            break;
    }

    Console.ReadLine();
}

这是我到目前为止的代码。 .txt文件显示它没有问题，但是在输入while语句并按选项时，它不会返回任何内容。

在arrText中存储.txt文件的单词，这些单词是：“在”，“在”，“在”时。

我需要在按下“ a”键时的while语句中，以字母顺序显示单词列表：“ are”“ in”“ while”。

Answer 1

我会提供一个更好的分离和缩短版本：

    var choices = new Dictionary<ConsoleKey, bool?>()
    {
        { ConsoleKey.D1, true },
        { ConsoleKey.D2, false }
    };

    var ascending = (bool?)null;
    while (ascending == null)
    {
        Console.WriteLine("Please choose between ascending and descending order.");
        Console.WriteLine("Press 1 for ascending");
        Console.WriteLine("Press 2 for descending");
        var choice = Console.ReadKey(true);
        ascending = choices.ContainsKey(choice.Key) ? choices[choice.Key] : null;
    }

    var lines = File.ReadAllLines("c:/data.txt");
    lines = ascending.Value
        ? lines.OrderBy(x => x).ToArray()
        : lines.OrderByDescending(x => x).ToArray();

    foreach (var line in lines)
    {
        Console.WriteLine(line);
    }
    Console.WriteLine("Press any key to continue...");
    Console.ReadKey(true);

甚至是这样：

    var choices = new Dictionary<ConsoleKey, Func<string[], string[]>>()
    {
        { ConsoleKey.D1, xs => xs.OrderBy(x => x).ToArray() },
        { ConsoleKey.D2, xs => xs.OrderByDescending(x => x).ToArray() }
    };

    var ascending = (Func<string[], string[]>)null;
    while (ascending == null)
    {
        Console.WriteLine("Please choose between ascending and descending order.");
        Console.WriteLine("Press 1 for ascending");
        Console.WriteLine("Press 2 for descending");
        var choice = Console.ReadKey(true);
        ascending = choices.ContainsKey(choice.Key) ? choices[choice.Key] : null;
    }

    var lines = ascending(File.ReadAllLines("c:/data.txt"));

    foreach (var line in lines)
    {
        Console.WriteLine(line);
    }
    Console.WriteLine("Press any key to continue...");
    Console.ReadKey(true);

Answer 2

这是我对你的问题的看法。注意，在循环文件中的文本之前，我正在询问排序顺序。

using System.Linq;
using System.IO;

class Program
{
    static void Main(string[] args)
    {
        var lines = File.ReadAllLines("c:/data.txt");
        var ascending = false;
        var chosen = false;
        do
        {
            Console.WriteLine("Please choose between ascending and descending order.");
            Console.WriteLine("Press 1 for ascending");
            Console.WriteLine("Press 2 for descending");
            var choice = Console.ReadKey(true);
            switch (choice.Key)
            {
                case ConsoleKey.D1:
                    ascending = true;
                    chosen = true;
                    break;
                case ConsoleKey.D2:
                    ascending = false;
                    chosen = true;
                    break;
                default:
                    Console.WriteLine("Invalid Choice");
                    break;
            }
        } while (!chosen);
        var sequence = ascending 
            ? lines.OrderBy(x => x) 
            : lines.OrderByDescending(x => x);
        foreach (var line in sequence)
        {
            Console.WriteLine(line);
        }
        Console.WriteLine("Press any key to continue...");
        Console.ReadKey(true);
    }
}

Answer 3

这也应该在对提供的示例代码进行最小更改的情况下起作用。

首先，将ArrayList更改为List<string>

List<string> arrText = new List<string>();

第二，使用List OrderBy或OrderByDescending方法进行订购

string ordenado = string.Format("{0}{1}{0}", "'", string.Join("','", arrText.OrderBy(x => x)));

Answer 4

使用ArrayList作为原始主题，List更加灵活，但是如果必须，则需要处理该类型的限制。

    public static void Main()
    {
        StreamReader objReader = new StreamReader(@"C:\\Temp\\data.txt");
        string orden = "";
        ArrayList arrText = new ArrayList();
        while (orden != null)
        {
            orden = objReader.ReadLine();
            if (orden != null)
                arrText.Add(orden);
        }
        objReader.Close();
        foreach (string sOutput in arrText)
        { Console.WriteLine(sOutput); }
        Console.WriteLine("Order alphabetically descendant press 'a': ");
        Console.WriteLine("Ordener ascending alphabetical press 'b': ");
        orden = Console.ReadLine();
        switch (orden)
        {
            case "a":
                arrText.Sort();
                break;
            case "b":
                arrText.Sort();
                arrText.Reverse();
                break;
        }

        foreach (string sTemp in arrText)
        { Console.Write(sTemp); }
        Console.WriteLine();
        Console.ReadLine();
    }

按字母顺序排列字符串

4 个答案: