Generate Codabar Barcodes
Aspose.BarCode for PHP via Java supports the Codabar type that allows encoding numerical characters and a set of six punctuation signs. Codabar barcodes may include four optional alphabet symbols (generally, A, B, C, or D) serving as start and stop characters. As such, this symbology supports four sets of start digits and four sets of stop ones. In this way, using the same input data, it is possible to create 16 barcodes with service sets of start and stop symbols.
Input text in Codabar barcodes has the following format:
[Start Character "A/B/C/D"] [Data Digits from the charset: "0-9" and "–$./:+"] [Stop Character "A/B/C/D"]
Start and Stop Symbols
Start and stop digits can be encoded separately using any of four formats (A, B, C, or D). To specify the preferred format, it is possible to use setCodabarStartSymbol and setCodabarStopSymbol functions from class CodabarParameters. The default set of start and stop digits is “A”.
Following barcode images have been created using various sets of start and stop characters.
|Start and Stop Characters||A+A||B+B||C+C||D+D|
By default, the Codabar standard does not require obligatory checksum controls. If checksum controls are needed, Codabar provides two checksum algorithms: Mod10 and Mod16. The pseudocode given below shows how these two checksum algorithms can be used.
//Mod10 foreach (var value in encodedCodetext) checkSum = (checkSum + value) % 10; //Mod16 foreach (var value in encodedCodetext) checkSum = (checkSum + value) % 16;
Checksum controls for Codabar can be enabled using the EnableChecksum class. The required checksum algorithm can be allocated through the CodabarChecksumMode enum. By default, the Mod16 checksum is applied.
Codabar barcode images below have been generated using different checksum control settings.
|Checksum||Is Set to None||Is Set to Mod10||Is Set to Mod16|