SetNullHandling

When to use

You can use this function to:

• Establish consistent behavior across all equations for handling empty parameter values.
• Set empty parameter values to zero (1) when calculations require numeric default values instead of null values.
• Set empty parameter values to zero (0) to avoid null-reference errors in mathematical operations.

When not to use

You cannot use this function if different equations require different null-handling behavior because the setting applies globally.

Syntax

void SetNullHandling(int value);

Parameter

Prerequisites

• This function sets a global flag for all equations.
• If you use this function for one equation, you must use it for all equations.
• The setting applies to all equations executed after this function is called.

Examples

Example 1

Treat Empty Values as Zero.

SetNullHandling(1);

Example 2

Using Flag = 1 (Zero) for Calculations.

// Treat empty values as zero for calculations
SetNullHandling(1);
// If PROTEIN parameter is empty, it's treated as 0
double protein = Convert.ToDouble(Param("PROTEIN"));  // Returns 0 if empty
double fat = Convert.ToDouble(Param("FAT"));          // Returns 0 if empty
// Calculate total (empty values don't cause null errors)
double total = protein + fat;
MessageList($"Total: {total}");  // Works even if parameters are empty

Example 3

Treat Empty Values as Null.

SetNullHandling(0);

Example 4

Using Flag = 0 (Null) for Null-Aware Logic.

// Treat empty values as null for null-aware logic
SetNullHandling(0);

// Check if parameter has a value
string proteinStr = Param("PROTEIN");

if (string.IsNullOrEmpty(proteinStr))
{
    MessageList("PROTEIN parameter is null/empty");
    // Handle null case
}
else
{
    double protein = Convert.ToDouble(proteinStr);
    MessageList($"PROTEIN value: {protein}");
}