如果进程花费的时间超过设置的时间间隔但不退出，C# 会做一些事情

Question

我有一个 .exe 进程，我想等待 2 小时才能完成。但是，如果花费的时间超过 1 小时，我想调用一个函数来发送电子邮件状态，这比平时花费的时间长。如果需要超过一定时间但没有退出进程并仍然等待整整 2 小时，如何调用函数？

我如何调用进程

var proc = System.Diagnostics.Process.Start(exePath, parameterString);
var procExited = proc.WaitForExit(twohourinmilliseconds);
//do something here if taking longer than 1 hour but not quit?
int exitCode = proc.ExitCode;

Answer 1

您可以尝试使用WaitForExit - WaitForExitAsync 的async 版本（也可以让async 成为日常工作）：

 var proc = System.Diagnostics.Process.Start(exePath, parameterString);

 // Delay for an hour (3_600_000 milliseconds)
 Task delay = Task.Delay(3_600_000);

 // Asynchronously wait for two possible outcomes: 
 //  1. process completion
 //  2. delay (timeout) completion  
 if (delay == await Task.WhenAny(proc.WaitForExitAsync(), delay)) {
   // 1 hour passed, but proc is still running
   //TODO: Send notification here
 } 
 else {
   // process completed before 1 hour passed
 }

如果您不想等待超过 2 小时（7_200_000 毫秒）并且您想在等待 1 小时后发送消息：

 var proc = System.Diagnostics.Process.Start(exePath, parameterString);

 // We are going to cancel proc after 2 hours (== 7_200_000 milliseconds)
 // for its completion
 using (CancellationTokenSource cs = new CancellationTokenSource(7_200_000)) {
   Task delay = Task.Delay(3_600_000, cs.Token);
   Task exe = proc.WaitForExitAsync(cs.Token);

   try {
     if (delay == await Task.WhenAny(exe, delay)) {
       // 1 hour passed, but proc is still running
       //TODO: Send notification here
     }
       
     // Keep on waiting exe
     await exe;  

     // proc succesfully completed; we are within 2 hours timeout 
     //TODO: implement normal flow here
   }
   catch (TaskCanceledException) {
     // 2 hours passed, proc execution cancelled  
     //TODO: you pobably want to send another message here
   }
 }