Can I Put Rules on Parameters?

[Crassius]

For example, I have a parameter that must be an integer.... that's easy, I can do that with type, but what if it needs to be an even integer?

I can force convert Odd to Even in code in the initialize event by changing an odd Parameter entered by the user to an even one, but is there a way to reject the Odd Parameter on user input, with some feedback to the user, so they know they have to select an even integer?

I can envision other times when such logic could be useful.

[NinjaTrader_RyanM1]

Hello Crassius,

Yes, this can be custom coded but would generally be outside our scope of support. You will likely want to look into the mod operator % which returns the remainder of two values.

We enforce minimum values for public inputs through the Set statement in the block below, so you could work within there to enforce even or odd.

[Description("Numbers of bars used for calculations")]
[GridCategory("Parameters")]
public int Period
{
get { return period; }
set { period = Math.Max(1, value); }
}


Example % operator:
if (someValue % 2 != 0)
Print("This value is not evenly divisible by 2");

[koganam]

For example, I have a parameter that must be an integer.... that's easy, I can do that with type, but what if it needs to be an even integer?

I can force convert Odd to Even in code in the initialize event by changing an odd Parameter entered by the user to an even one, but is there a way to reject the Odd Parameter on user input, with some feedback to the user, so they know they have to select an even integer?

I can envision other times when such logic could be useful.

Divide the integer by 2, then multiply the result by 2. If the number is odd, the division will discard the half, so when you multiply the result by 2, you will end up with an even number.

[Crassius]

Thank you both for the quick responses.

[NinjaTrader_RyanM1]

Forces Even by adding 1 if it detects an odd value.

[Description("Numbers of bars used for calculations")]
[GridCategory("Parameters")]
public int Period
{
get { return period; }
set { period = Math.Max(1, value % 2 == 0 ? value: value + 1); }
}

Forces Odd by adding 1 if it detects an even value.

[Description("Numbers of bars used for calculations")]
[GridCategory("Parameters")]
public int Period
{
get { return period; }
set { period = Math.Max(1, value % 2 == 1 ? value: value + 1); }
}