Introduction Class TWPCustomRTFControl Class TWPRichText Class TWPCustomRichText Class TDBWPRichText Class TWPCustomRtfEdit Class TWPPreview Class TWPRichTextLabel
Class TWPToolbar Class TWPToolButton Class TWPToolPanel Class TWPVertRuler Class TWPRuler Class TWPGutter
Class TTextHeader Class TWPRTFSectionProps Class TWPOwnedCharAttrInterface Class TWPStoredCharAttrInterface Class TWPAbstractCharAttrInterface Class TWPAbstractCharParAttrInterface Class TWPCursorCharAttrInterface Class TWPFoundTextAttrInterface Class TWPCurrentWritingmodeAttrInterface
Class TWPRTFReaderEx Class TWPRTFReader Class TWPRTFWriter Class TWPRTFWriterEx Class TWPToolsReaderWriter Class TWPTextWriter Class TWPHTMLWriter Class TWPTOOLSWriter Class TWPUNITextWriter Class TWPCustomTextWriter Class TWPTextReader Class TWPHTMLReader Class TWPTOOLSReader Class TWPUNITextReader Class TWPCustomTextReader
Class TWPRTFDataCollectionBase Class TWPRTFDataCollection Class TWPRTFDataBlock Class TWPRTFDataBlockEd Class TParagraph Class TWPTextStyle Class TWPORTFTextBox Class TWPObjectField Class TWPObject Class TWPRTFEngineBasis Class TWPRTFEngineEdit
Class TWPManageHeaderFooterDlg Class TWPPagePropDlg Class TWPParagraphBorderDlgEx Class TWPParagraphBorderDlg Class TWPTabDlgPrp Class TWPOneStyleDlg Class TWPBulletDlg Class TWPSymbolDlg Class TWPSymbolDlgEx Class TWPSpellCheckDlg Class TWPStringDlg Class TWPStyleDlg Class TWPCustomAttrDlg Class TWPSearchReplaceDlg Class TWPParagraphPropDlg Class TWPPreviewDlg Class TWPReportBandsDialog Class TWPTableDlg
Class TWPSuperMerge Class TDBWPEvalEngine Class TWPEvalEngine Class TWPTableProducer Class TWPBand Class TWPDataSetAbstractAdapter
Class TWPSvgXMLNode Class TWPXMLOneLevel Class TWPCustomXMLInterface Class TWPXMLInterface Class TWPLanguageControl Class TWPXMLTree Class TWPSVGXMLTree Class TWPCustomXMLTree
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Class TWPEvalEngine

Hierarchy

System.TObject | System.Classes.TPersistent | System.Classes.TComponent | WPEval.TWPCustomEvalEngine | TWPEvalEngine

Description for Class TWPCustomEvalEngine

The component TWPEvalEngine can be used to calculculate currency values in mail merge operation and also within text tables. To use it on tables you need to add the component TWPFormularInterface (unit WPTableCalc).
Esspecially the use in tables makes sense since you can here read out neighbour cells, i.e. add the VAT: "left(1)*1.19" would take the cell to the left and multiply it by 1.19.
You can also read out table cells by just using the name, i.e. "A". When you use "A" in a forumula it will be set equal to the sum of all cells with the name A.
In unit WPEval you will find the functions which are available, i.e. wpevSin() which is mapped to Sin().
There is also the unit WPDBEval which acts as interface to a dataset. It makes it possible to read out dataset fields and use in calculation. For this the dataset must be registered with the WPDBEvalEngine.
To register a data set with the TDBWPEvalEngine use DBWPEvalEngine.AddDataSet( Alias, Dataset)
The Alias will be expected before the . in a field name, i.e PRODUCTS.PRICE will read out the field price of the table products

Events

OnDBCommand : TWPExecuteDatabaseCommand= TWPExecuteDatabaseCommand

OnError : TWPEvalErrorEvent= TWPEvalErrorEvent

OnFunction : TWPReadFunctionResult= TWPReadFunctionResult

OnGetErrorMessage : TWPEvalGetErrorMessage= TWPEvalGetErrorMessage

OnProcessMessages : TNotifyEvent= procedure (Sender : TObject) of Object

OnReadVariable : TWPReadVariableValue= TWPReadVariableValue

OnWriteVariable : TWPWriteVariableValue= TWPWriteVariableValue

Used or referenced by

-Property TWPEvalType.Engine : TWPCustomEvalEngine
-Property TWPEvalType.Engine : TWPCustomEvalEngine