TUserDefinedFunction.Evaluate Method
Override this method to provide your own implementation on the function.
If this method throws an exception, it will not be handled and the recalculation will be aborted. So if you want to return an error, return a TFlxFormulaErrorValue value.
Do not use any global variable in this method, it must be stateless and always return the same value when called with the same arguments.
See 'Using excels user defined functions udf' in the Api Developer Guide for more information.
Syntax
Unit: FlexCel.Core
function TUserDefinedFunction.Evaluate(const arguments: TUdfEventArgs; const parameters: TArray<TFormulaValue>): TFormulaValue; virtual; abstract;Parameters
| <-> | Parameter | Type | Description |
|---|---|---|---|
| const | arguments | TUdfEventArgs | Extra objects you can use to evaluate the function. |
| const | parameters | TArray<TFormulaValue> | Parameters for the function. When this method is called by FlexCel, this parameter will never be null, but might be an array of zero length if there are no parameters. Each parameter in the array will always be a TFormulaValue This class provides utility methods like TryGetDouble that will help you get an specific type of object from a parameter. |
Returns
Return any object you want here. Normally a double, a string, a boolean a TFlxFormulaErrorValue or a null. If this method returns a class, it will be converted to an allowed value, normally to a string. If you want to return an array for an array formula, return a 2-dimensional array in the result, where the elements of the array are the values you want to return.
Examples
See 'Using excels user defined functions udf' in the Api Developer Guide for examples.