C#线程方法名称预期错误

本文关键字:错误 线程 方法 | 更新日期: 2023-09-27 18:29:29

我正在尝试创建一个简单的线程过程(假设这是我第一次尝试线程),我只想让它对字符串[]中的每个字符串执行一个void并执行简单的文件夹爬网。然而,我收到了预期的方法名称,我不确定的原因

string[] FileListing = {@"C:'","E:'"};
        foreach (string fl in FileListing)
        {
            ProjectDirectoryProcessing pjp = new ProjectDirectoryProcessing();
            //error here
            Thread oThread = new Thread(new ThreadStart(pjp.ProjectProcessor(fl)));
            oThread.Start();
        }
public class ProjectDirectoryProcessing
{
    public void ProjectProcessor(string rootDirectory)
    {
        Stopwatch stopwatch = new Stopwatch();
        stopwatch.Start();
        HashSet<string> DirectoryHolding = new HashSet<string>();
        //do some work
        //foreach loop
    };
  }

C#线程方法名称预期错误

您必须将委托传递给线程构造函数。在这里,最简单的方法是使用lambda表达式:

string copy = fl;
Thread oThread = new Thread(() => pjp.ProjectProcessor(copy));

请注意,由于捕获循环变量的方式,您需要制作循环变量的副本。(更多详细信息,请参阅Eric Lippert的博客文章。)

或者,当您在每次迭代中创建一个新的ProjectDirectoryProcessing实例时,您可以将字符串传递给构造函数

foreach (string fl in FileListing)
{
    // Note change in name to be clearer (IMO)
    ProjectDirectoryProcessor pjp = new ProjectDirectoryProcessor(fl);
    Thread oThread = new Thread(pjp.Execute);
    oThread.Start();
}

public class ProjectDirectoryProcessor
{
    private readonly string rootDirectory;
    public ProjectDirectoryProcessor(string rootDirectory)
    {
        this.rootDirectory = rootDirectory;
    }
    public void Execute()
    {
        Stopwatch stopwatch = Stopwatch.StartNew();
        HashSet<string> DirectoryHolding = new HashSet<string>();
        // do some work
        //foreach loop
    }
}

您需要传入委托,可以使用lambda:

 Thread oThread = 
      new Thread( () => pjp.ProjectProcessor(fl));

但随后您将捕获一个循环变量,因此将其设为

    foreach (string fl in FileListing)
    {
        string copy = fl;
        ProjectDirectoryProcessing pjp = new ProjectDirectoryProcessing();
        //error here
        Thread oThread = 
          new Thread( () => pjp.ProjectProcessor(copy));
        oThread.Start();
    }

附加

每次制作一个线程都很昂贵,你可能更擅长使用:

    Parallel.ForEach(FileListing, fl => 
      {            
        ProjectDirectoryProcessing pjp = new ProjectDirectoryProcessing();         
        pjp.ProjectProcessor(fl);
      } );
    // when here: all threads are done. 

请注意,pjp现在已在线程上创建。

Thread oThread = new Thread(new ThreadStart(pjp.ProjectProcessor(fl)));

您实际上是在将void作为参数传递给ThreadStart构造函数。

它必须是线程吗?任务更适合这种情况。交换:

Thread oThread = new Thread(new ThreadStart(pjp.ProjectProcessor(fl)));
oThread.Start();

带有:

Task.Factory.StartNew(pjp.ProjectProcessor(fl));