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
};
}
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));