Single Instance Strategy/Indicator/Addon

[jeronymite]

I need to be able to restrict a Strategy/Indicator in both NT7 and NT8 and an Addon in NT8 to run only a single instance.

I have code for a thread-safe Singleton as follows:

[FONT="Courier New"]
public sealed class Singleton
{
	private static volatile Singleton instance;
	private static object syncRoot = new Object();
	
	private Singleton() {}
	
	public static Singleton Instance
	{
		get 
		{
			if (instance == null) 
			{
				lock (syncRoot) 
				{
				if (instance == null) 
					instance = new Singleton();
				}
			}
			
			return instance;
		}
	}
}
[/FONT]

which I use like this:

[FONT="Courier New"]
Singleton single = Singleton.Instance;
if (single == null) // ... Exit appropriately
[/FONT]

I also have code for a Mutex approach:

[FONT="Courier New"]
public static Mutex mutex  = new Mutex(true,"MyDogHasFleas") ;
public static bool SingleOut()
{
	if (mutex.WaitOne(TimeSpan.Zero,true))
	{
		mutex.ReleaseMutex() ;
		return true ;
	}
	else
	{
		MessageBox.Show("Only one instance at a time!") ;
		return false ;
	}
}
[/FONT]

which I use like this:

[FONT="Courier New"]
bool solo = SingleOut();
if (!solo) // ... Exit appropriately
[/FONT]

This all sits in the (Public or Partial) Strategy class.

I cannot seem to make either approach work.In both approaches, I can run a strategy several times and each runs without detecting any previous instance.

I am obviously doing something wrong and would appreciate advice on getting both approaches working in NT7 and NT8.

Thanks.

[NinjaTrader_ChelseaB]

Hello jeronymite,

This custom code is beyond what our support is able to assist with, however, I do have an example of using a static property to share information between indicator / strategy instances.

https://ninjatrader.com/support/forum/showthread.php?p=442980#post442980

This thread will remain open for any community members that would like to assist.

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