控制任务的开始，停止和重新启动
我想创建一个循环连接检查任务（在连接启动后启动）这两个函数都可以工作，但我不知道如何重新启动之前执行的任务。 基本上这是我想要实现的：
创建任务循环
我只能直接启动任务，任何尝试创建任务并稍后执行都会失败。 还重新启动先前执行的任务失败。 任何人都可以帮助我，是否有可能实现我的目标？ 如果是的话，这是正确的方向，还是我做结构错误？ 这让我烦恼几天，任何帮助或提示将不胜感激。
class Program
{
static void Main(string[] args)
{
Task<ReturnResult> ConnectionStartResult = CommManager.StartAllConnections();
Task<List<ReturnResult>> ConnectionCheckResult = CommManager.CreateConnectionCheckTask();
//Task<List<ReturnResult>> ConnectionCheckResult = CommManager.StartConnectionCheck();
ConnectionStartResult.ContinueWith((prevTask) =>
{
CommManager.ValueListerStart();
//ConnectionCheckResult.Start();
});
ConnectionCheckResult.ContinueWith((myPreviusTask) =>
{
CommManager.ValueListerStop();
Console.WriteLine("Connection problems found");
ConnectionStartResult = CommManager.StartAllConnections();
});
}
}
public class CommManager
{
private static CancellationTokenSource CommCheckTokenSource;
// starts connections in the background, end when done
public static async Task<ReturnResult> StartAllConnections()
{
ReturnResult result = await Task.Run(() => ConnectAll());
return result;
}
private static ReturnResult ConnectAll()
{
Thread.Sleep(1000);
return new ReturnResult();
}
// start and run connection check. Works, but i cannot recall this after connection problem
public static async Task<List<ReturnResult>> StartConnectionCheck()
{
CommCheckTokenSource = new CancellationTokenSource();
var CommCheckToken = CommCheckTokenSource.Token;
return await Task.Run(() => CheckPlcConnectionsTask(CommCheckToken));
}
// only create task. (but do not start) works but locks up the UI thread, whan started in main
public static Task<List<ReturnResult>> CreateConnectionCheckTask()
{
CommCheckTokenSource = new CancellationTokenSource();
var CommCheckToken = CommCheckTokenSource.Token;
return new Task<List<ReturnResult>>(() => CheckPlcConnectionsTask(CommCheckToken));
}
// the connection check function
private static List<ReturnResult> CheckPlcConnectionsTask(CancellationToken token)
{
var returnList = new List<ReturnResult>();
while (!token.IsCancellationRequested)
{
// keep checking connection only return when disconnect is found
Thread.Sleep(3000); // for test
return returnList;
}
return returnList;
}
public static void ValueListerStart()
{ }
public static void ValueListerStop()
{ }
}
public class ReturnResult
{ }