HPDFBarcode Unit Reference

The HPDFBarcode unit exposes the barcode component and low-level bar encoder helpers used by THPDFPage.DrawBarcode

Use THPDFPage.DrawBarcode for direct PDF page output, use THPDFBarcode when rendering to a VCL TCanvas, and use the Simple* functions when an application needs the generated bar sequence before drawing

THPDFBarcode

THPDFBarcode is a TComponent descendant that renders a configured barcode to a VCL canvas and can optionally draw the human-readable text label

Member	Usage
`Assign`	Copies barcode configuration from another persistent object
`DrawBarcode`	Draws the bars for the configured barcode on the supplied TCanvas
`DrawText`	Draws the optional text label on the supplied TCanvas
`CanvasHeight`	Returns the rotated drawing height needed for the configured Width, Height, and Angle
`CanvasWidth`	Returns the rotated drawing width needed for the configured Width, Height, and Angle

Published Properties

The component publishes layout, barcode type, checksum, colour, text-label, and change notification settings

Property	Usage
`Height`, `Width`	Set the barcode drawing height and read or assign the calculated barcode width
`Text`	Supplies the barcode payload as an AnsiString
`Top`, `Left`	Set the canvas origin for the barcode output
`Modul`	Sets the base module width used when bars are painted
`Ratio`	Sets the wide-to-narrow bar ratio used by supported symbologies
`Typ`	Selects the barcode type by the ordinal value of THPDFBarcodeType
`Checksum`, `CheckSumMethod`	Enable checksum output and choose csmNone or csmModulo10
`Angle`	Rotates the rendered barcode
`ShowText`, `ShowTextFont`, `ShowTextPosition`	Control whether the readable text is drawn, which font is used, and where the label is placed
`Color`, `ColorBar`	Set the background colour and bar colour
`OnChange`	Receives a TNotifyEvent when a property setter changes barcode state

Barcode Types and Options

Type	Values
`THPDFBarcodeType`	`bcCode_2_5_interleaved`, `bcCode_2_5_industrial`, `bcCode_2_5_matrix`, `bcCode39`, `bcCode39Extended`, `bcCode128A`, `bcCode128B`, `bcCode128C`, `bcCode93`, `bcCode93Extended`, `bcCodeMSI`, `bcCodePostNet`, `bcCodeCodabar`, `bcCodeEAN8`, `bcCodeEAN13`, `bcCodeUPC_A`, `bcCodeUPC_E0`, `bcCodeUPC_E1`, `bcCodeUPC_Supp2`, `bcCodeUPC_Supp5`, `bcCodeEAN128A`, `bcCodeEAN128B`, `bcCodeEAN128C`
`THPDFBarcodeOption`	`bcoNone`, `bcoCode`, `bcoTyp`, `bcoBoth`
`THPDFShowTextPosition`	`stpTopLeft`, `stpTopRight`, `stpTopCenter`, `stpBottomLeft`, `stpBottomRight`, `stpBottomCenter`
`THPDFCheckSumMethod`	`csmNone`, `csmModulo10`
`THPDFBarLineType`	`white`, `black`, `black_half`

Simple Bar Records

The simple encoder functions return their generated bars through TSimpleBarArray, an array of TSimpleBarcodeBar records

Record	Fields
`TSimpleBarcodeBar`	Width contains the module width contribution, and Filled identifies whether the segment is a printed bar
`TSimpleBarArray`	Dynamic array of TSimpleBarcodeBar values filled by the Simple* functions

Simple Encoder Functions

Each function has the signature function Name(const Text: AnsiString; var Bars: TSimpleBarArray): Integer and returns the total generated bar width

Group	Functions
Code 2/5	`SimpleCode25Interleaved`, `SimpleCode25Industrial`, `SimpleCode25Matrix`
Code 39 and Code 93	`SimpleCode39`, `SimpleCode39Extended`, `SimpleCode93`, `SimpleCode93Extended`
Code 128 and EAN-128	`SimpleCode128A`, `SimpleCode128B`, `SimpleCode128C`, `SimpleEAN128A`, `SimpleEAN128B`, `SimpleEAN128C`
Retail and postal	`SimpleEAN8`, `SimpleEAN13`, `SimpleUPC_A`, `SimpleUPC_E0`, `SimpleUPC_E1`, `SimpleUPC_Supp2`, `SimpleUPC_Supp5`, `SimplePostNet`
Other supported symbologies	`SimpleMSI`, `SimpleCodebar`

Example

var
  Bars: TSimpleBarArray;
  TotalWidth: Integer;
begin
  TotalWidth := SimpleCode128B('ABC-123', Bars);
end;

See also