等待多个进程完成

Question

我希望我的程序等待所有进程完成,然后删除一些临时文件.我已经有一段代码可以在一次处理一个进程时执行此操作,但我无法使其适用于多个进程.

我将首先展示有效的代码.此代码正确运行进程,等待它完成,然后删除临时文件:

foreach (string script in scriptList)
{
     ProcessStartInfo myProcess = new ProcessStartInfo();
     myProcess.FileName = accoreconsolePath;
     myProcess.Arguments = "/s \"" + script + "\"";
     myProcess.CreateNoWindow = true;         
     Process myWait = Process.Start(myProcess);
     myWait.WaitForExit();

     File.Delete(script);            
}  

以上内容整齐地包含在foreach循环中.我无法工作的是这样的并行版本,其中wait语句在foreach循环之外:

  Process myWait;
  foreach (string script in scriptList)
  {
     ProcessStartInfo myProcess = new ProcessStartInfo();
     myProcess.FileName = accoreconsolePath;
     myProcess.Arguments = "/s \"" + script + "\"";
     myProcess.CreateNoWindow = true;
     myWait = Process.Start(myProcess);
  }
  myWait.WaitForExit();                             //error: use of unassigned local variable "myWait"
  //delete file would go here

我想我只需要myWait在进入foreach循环之前初始化,但我不知道该怎么做.如何在不将其分配给任何内容的情况下初始化流程？还有其他一些简单的方法吗？

Answer 1

不确定这种方法是否出现在评论的任何相关问题中,但这里有一个使用List<Task>和Task.WaitAll():

List<Task> tasks = new List<Task>();            
foreach (string script in scriptList)
{
    string tmpScript = script;
    tasks.Add(Task.Run(delegate {
        ProcessStartInfo myProcess = new ProcessStartInfo();
        myProcess.FileName = accoreconsolePath;
        myProcess.Arguments = "/s \"" + tmpScript + "\"";
        myProcess.CreateNoWindow = true;
        Process.Start(myProcess).WaitForExit();
        File.Delete(tmpScript);
    }));
}
Task.WaitAll(tasks.ToArray());

Answer 2

我会将进程句柄存储在脚本与进程句柄的字典中，然后等待所有进程退出。下面是代码：

var processes = new Dictionary<string,Process>();

foreach (string script in scriptList)
{
    ProcessStartInfo myProcess = new ProcessStartInfo();
     myProcess.FileName = accoreconsolePath;
     myProcess.Arguments = "/s \"" + script + "\"";
     myProcess.CreateNoWindow = true;
     myWait = Process.Start(myProcess);
     processes.Add(script, myWait);
}

foreach(var script in processes.Keys)
{
    Process process = processes[script];

    process.WaitForExit();
    process.Close();

    File.Delete(script);
}