Class AbstractCalculationEngine

AbstractCalculationEngine class

Represents user’s custom calculation engine to extend the default calculation engine of Aspose.Cells.

public abstract class AbstractCalculationEngine

Properties

Name	Description
virtual IsParamArrayModeRequired { get; }	Indicates whether this engine needs the parameter to be calculated in array mode. Default value is false. If `GetParamValueInArrayMode` is required when calculating custom functions and user has not updated the definition for them (by `UpdateCustomFunctionDefinition`), this property needs to be set as true.
virtual IsParamLiteralRequired { get; }	Indicates whether this engine needs the literal text of parameter while doing calculation. Default value is false.
virtual ProcessBuiltInFunctions { get; }	Whether built-in functions that have been supported by the built-in engine should be checked and processed by this implementation. Default is false.

Methods

Name	Description
abstract Calculate(CalculationData)	Calculates one function with given data.
virtual ForceRecalculate(string)	Whether force given function to be recalculated always when calculating shared formulas.

Remarks

User should not modify any part of the Workbook directly in this implementation(except the calculated result of the custom function, which can be set by CalculationData.CalculatedValue property). Otherwise unexpected result or Exception may be caused. If user needs to change other data than calculated result in the implementation for some custom functions, for example, change cell’s formula, style, …etc., user should gather those data in this implementation and change them out of the scope of formula calculation.

Examples

[C#]
Workbook wb = new Workbook("custom_calc.xlsx");
CalculationOptions opts = new CalculationOptions();
opts.CustomEngine = new MyEngine();
wb.CalculateFormula(opts);

class MyEngine : AbstractCalculationEngine
{
    public override void Calculate(CalculationData data)
    {
        string funcName = data.FunctionName.ToUpper();
        if ("MYFUNC".Equals(funcName))
        {
            //do calculation for MYFUNC here
            int count = data.ParamCount;
            object res = null;
            for (int i = 0; i < count; i++)
            {
                object pv = data.GetParamValue(i);
                if (pv is ReferredArea)
                {
                    ReferredArea ra = (ReferredArea)pv;
                    pv = ra.GetValue(0, 0);
                }
                //process the parameter here
                //res = ...;
            }
            data.CalculatedValue = res;
        }
    }
}