信号量C＃两个线程

Question

我的代码的想法是将文件写入文件（.txt）然后读取该文件，如果读取的字母是辅音，则输出它。如果没有，什么都不做。

我正在使用信号量来做到这一点。创建了两个线程。它从文件写入和读取。但是，无法运行此条件。出于某种原因，从文件中读取时会显示转换错误。并且“letter”变量等于'\ 0'。

namespace Sema
{
class Program
{
    private static Semaphore sPhore  = new Semaphore(2, 2);
    public static string path = "message.txt";

    private static void write(object input)
    {


        Console.WriteLine("\nEnter the consonant: ");
        sPhore.WaitOne();
        input = Console.ReadLine();
        TextWriter tw = File.CreateText(path);
        tw.WriteLine(input);
        tw.Close();
        sPhore.Release();
    }
    private static void read(object input)
    {
        sPhore.WaitOne();
       char letter = Convert.ToChar(File.ReadAllLines(path));
       //char letterChar = Convert.ToChar(letter);
        if (letter.Equals('q') || letter.Equals('w') || letter.Equals('r') || letter.Equals('t') || letter.Equals('p') || letter.Equals('s')
         || letter.Equals('d') || letter.Equals('f') || letter.Equals('g') || letter.Equals('h') || letter.Equals('j') || letter.Equals('k') 
         || letter.Equals('l') || letter.Equals('z') || letter.Equals('x') || letter.Equals('c') || letter.Equals('v') || letter.Equals('b') 
         || letter.Equals('n') || letter.Equals('m')) 
        {
            Console.WriteLine("\nYou wrote this consonant:" + letter);
        }

            //TextReader tr = File.OpenText("message.txt");
        //Console.Write("\nYou wrote this char:" + tr.ReadAsync());
        //tr.Close();
        sPhore.Release();
    }
    //private static void read(object path) 
    //{

    //}
    static void Main(string[] args)
    {

        for (int i = 0; i < 4; i++)
        { 
            Thread ss = new Thread(new ParameterizedThreadStart(write));
            Thread sss = new Thread(new ParameterizedThreadStart(read));
            ss.Start(i);
            ss.Join();
            sss.Start(i);
            sss.Join();
        }
        Console.ReadLine();
    }
}

}

Answer 1

读取所有行返回string []。为了将其转换为char，您需要从第一行获取第一行和第一个char：

    char letter = File.ReadAllLines(path)[0][0];