Documentation – Developer Guide

Javascript-Cpp: Barcode Generation Basics - Create Barcodes in JavaScript

Mon, 01 Jan 0001 00:00:00 +0000

Generate Barcodes Online. Test the quality of Aspose.BarCode generation and view the results online.

This chapter covers the basics of barcode generation and related topics, including supported barcode types, appearance customization, managing barcode size, customizing barcode text, saving generated barcodes, and more. Find detailed information in the articles below.

Article	Description
Set Barcode Size and Resolution	Details how to customize barcode measurement units and the resolution of generated images
Adjust Barcode Appearance	Explains how to adjust properties like size, rotation angle, padding, borders, and bar width reduction
Manage Barcode Text	Covers managing barcode text and captions, including visibility, position, font, spacing, and wrapping
Save Generated Barcodes	Describes how to save barcode images to streams, files, or bitmaps in various output formats (raster and vector)
Set Checksum Controls in 1D Barcodes	Explains checksum settings for 1D barcodes
Work with Barcode Generation State in XML	Describes how to import and export barcode generation state using XML

Javascript-Cpp: Barcode Generation Specifics in JavaScript

Mon, 01 Jan 0001 00:00:00 +0000

Introduction

This section provides an overview of barcode symbologies, their key properties, and examples of barcode labels and code snippets for generating various barcode types.

Overview

A barcode is a visual code made up of parallel lines, spaces of varying widths, or other shapes arranged in a pattern to represent data. Once generated and printed, barcode labels are placed on surfaces for scanning. Barcodes are machine-readable tags designed for quick data retrieval from visual patterns. A single barcode can encode about 25 characters for 1D types or up to 2,000 characters for 2D types. The more characters a barcode holds, the larger its size.

For any questions or clarifications, please contact Aspose Technical Support. Join discussions at the Aspose.Barcode Forum or reach out to Aspose Paid Support Helpdesk.

Barcodes vs RFID

Barcodes are read by sensors in scanners that emit light beams to detect the black and white lines in the barcode label. These scanners require a line-of-sight to scan one barcode at a time and convert the light signals into readable text.

RFID (Radio-Frequency Identification) is an alternative technology that uses radio waves to transfer data from RFID tags to readers. RFID tags have sensors with unique IDs, allowing a reader to scan multiple tags simultaneously without line-of-sight.

RFID systems are more suitable for scanning large quantities of items but come with higher costs and more complex setups. They also have limitations when used with metals or liquids. Barcodes, on the other hand, provide higher accuracy and reliability, as they ensure precise data reading, even if they cannot scan multiple items at once.

Barcode Usage

Barcodes are used in a variety of industries, including retail, healthcare, logistics, pharmacy, documentation management, and more. Below are examples of common business applications for barcodes:

Inventory tracking: This involves using barcode scanners or mobile devices paired with specialized software. Each item is tagged with a unique barcode, allowing for easy tracking of all operations related to that item.
Asset tracking: Businesses often need to manage assets efficiently. Placing barcode tags on assets and scanning them helps track and manage these items, improving accountability and simplifying audits.
Billing and invoice management: Barcodes can be linked to customer numbers or invoice identifiers, making it easy to access and process customer or invoice data.
Admission management: Tickets for events, travel itineraries, and similar documents can have barcodes for quick verification, speeding up admission processes and reducing printing costs.
Data storage: Barcodes, especially QR codes, are commonly used to store business and personal information. Smartphones can easily read these barcodes, providing fast and straightforward access to data.

Barcode Type Definition

Barcode types determine how data is encoded within the barcode image. Each type uses a unique method for encoding characters.

One-dimensional (1D) barcodes, or linear barcodes, encode data by varying the width and spacing of parallel lines.

Two-dimensional (2D) barcodes were developed to overcome the limitations of 1D barcodes. They use patterns such as rectangles, dots, hexagons, or other geometric shapes called matrix codes.

Postal barcodes refer to specific symbologies used by postal services across different countries. Unlike 1D barcodes, postal barcodes encode data by adjusting the height of bars. This allows them to encode information like ZIP and ZIP+4 codes and delivery addresses, which postal services process using automated scanning equipment.

Key Barcode Properties

Barcode symbologies share similarities with file formats, as they define essential barcode properties:

Data encoding format: Different barcode types have varying capabilities for encoding characters. Some can only encode numerical digits, others can handle alphabetic and special characters, while others support full encoding sets.
Data density: Each symbology has a defined capacity for encoding information, resulting in barcodes with either high or low data density.
Shape: Barcodes can come in different shapes, such as rectangular, square, or elongated.
Recognition precision: Certain 1D barcodes lack checksums and controls, making it difficult to verify that all data has been correctly read and decrypted. This results in lower recognition precision. Conversely, 2D barcodes offer higher recognition precision, as they include mechanisms to recover partially corrupted data and ensure accurate reading.

Supported Barcode Types

The following are the barcode types supported by Aspose.BarCode for JavaScript via C++.

Supported Symbologies
1D
Numerical Only	Code 11, Code 32, Codabar, Databar Omnidirectional, Databar Stacked Omnidirectional, Databar Limited, Databar Truncated, Databar Stacked, EAN 13, EAN 14, EAN 8, IATA 2-of-5, Italian Post 25, Interleaved 2-of-5, ISBN ISMN, ISSN, ITF 6, ITF 14, Matrix 2-of-5, MSI, OPC, PatchCode, Pharmacode, PZN, SSCC 14, SSCC 18, Standard 2-of-5, EAN 5, EAN 2, UPC-A, UPC-E, UpcaGs1DatabarCoupon
Alpha-Numeric	Code 128, Code 39, Code 93, Code 16K, CodablockF, Databar Expanded, Databar Expanded Stacked, GS1 CodablockF, GS1 Code 128, VIN
2D	QR Code, Micro QR Code, PDF417, Compact PDF417, Macro PDF417, Micro PDF417, Aztec, DataMatrix, DotCode, GS1 Data Matrix, GS1 QR Code, MaxiCode, DotCode, Han Xin Code
Postal	Australia Post, Australian Post Parcel, Deutsche Post Identcode, Deutsche Post Leticode, Planet, Postnet, RM4SCC, Singapore Post, Swiss Post Parcel, USPS OneCode

Set Barcode Type in Aspose.BarCode

Aspose.BarCode for JavaScript via C++ supports most widely used barcode symbologies. To generate a barcode image, create an instance of the BarcodeGenerator class and set two main parameters: the data to be encoded in the CodeText property and the barcode type in the BarcodeType property. The BarcodeType property specifies the symbology used for generating barcodes. Developers can select any supported symbology from the predefined list in the BarcodeGenerator class. However, not all symbologies support all text formats due to inherent limitations.

Code 39

Code 39 is a variable-length barcode symbology limited to 43 characters, including uppercase letters (A-Z), numerical digits, and some special characters (-, ., $, /, +, %, and space). Each character is represented by nine elements: five bars and four spaces. This symbology has low data density and does not include a mandatory checksum, which can affect recognition accuracy.

Below is a code snippet to generate a barcode using the Code 39 symbology.

How to get BarCodeInstance

// Generate a Code39Extended barcode
var gen = new BarCodeInstance.BarcodeGenerator("Code39FullASCII", "$&This Code#*");
document.getElementById("img").src = gen.GenerateBarCodeImage(); // Display barcode image

gen.delete();

Data Encoding Formats

Barcode symbologies use different data encoding techniques and have varied capabilities. The barcode label size and the data amount to be encoded are defined for each symbology. Some barcode types can only encode numerical digits or limited character sets, while others can encode any byte sequence without restrictions.

Below, we present examples of different barcode types, such as EAN 13, Code 11, GS1 Code 128, and PDF417, which showcase various data densities.

EAN 13

EAN 13 barcodes are designed to encode only numerical digits. Specifically, the data encoding format for EAN 13 requires encoding exactly 12 digits, with the 13th digit serving as a control sum calculated based on a specific algorithm.

Here’s an example code snippet to generate EAN 13 barcodes.

How to get BarCodeInstance

// Generate an EAN13 barcode
var gen = new BarCodeInstance.BarcodeGenerator("EAN13", "1234567890128");
gen.Parameters.Barcode.XDimension = "2px";
document.getElementById("img").src = gen.GenerateBarCodeImage(); // Display barcode image

gen.delete();

Code 11

The Code 11 symbology supports encoding a string of any length (theoretically unlimited), including numeric digits and the dash (-) character.

The following code sample shows how to generate a Code 11 barcode.

How to get BarCodeInstance

// Generate a Code11 barcode
var gen = new BarCodeInstance.BarcodeGenerator("Code11", "1234-5678");
document.getElementById("img").src = gen.GenerateBarCodeImage(); // Display barcode image

gen.delete();

GS1 Code 128

GS1 Code 128 can encode any ASCII alphanumeric characters, similar to the standard Code 128 symbology. However, the data encoding format in GS1 Code 128 follows strict GS1 standards.

The code example below demonstrates how to create a GS1 Code 128 barcode.

How to get BarCodeInstance

// Generate a GS1 Code128 barcode
var gen = new BarCodeInstance.BarcodeGenerator("GS1Code128", "(02)04006664241007(37)1");
gen.Parameters.Barcode.XDimension = "2px";
document.getElementById("img").src = gen.GenerateBarCodeImage(); // Display barcode image

gen.delete();

Data Density

Data density is a key property of barcode symbologies, indicating how much information can be stored in a single barcode. It is typically low for 1D barcodes and significantly higher for 2D matrix barcodes, with 2D barcodes offering over 10 times more data capacity than 1D symbologies.

Barcode Shapes

Barcodes can be printed on various surfaces and have different shapes. However, barcodes themselves are typically limited to rectangular or square forms. Using a square barcode in an area meant for a large, rectangular space is not efficient in terms of space usage.

Barcode Recognition Precision

Sometimes, data read from barcodes can be incorrect. 1D barcodes often do not include a checksum or only have basic error checks, making them more susceptible to errors. In contrast, most 2D barcodes use Reed-Solomon error correction, which helps ensure accurate reading and can recover data from partially damaged barcodes.

Interleaved 2-of-5

Interleaved 2-of-5 can encode digit sequences of any length, provided the sequence has an even number of digits. By default, it does not include a checksum, making it possible to read erroneous data.

The code example below shows how to generate an Interleaved 2-of-5 barcode.

How to get BarCodeInstance

// Generate an Interleaved 2 of 5 barcode
var gen = new BarCodeInstance.BarcodeGenerator("Interleaved2of5", "1234567890");
document.getElementById("img").src = gen.GenerateBarCodeImage(); // Display barcode image

gen.delete();

Postal Types

Postal symbologies are specialized barcode types designed exclusively for postal services. They typically have lower data density than 2D barcodes and can encode only numerical characters. Unlike traditional barcodes, postal symbologies often encode information by varying the height of bars. While many postal services are transitioning to widely used 2D barcodes, this change is gradual. Aspose.BarCode for JavaScript via C++ supports key postal symbologies along with 1D and 2D barcodes.

Postnet

The Postnet symbology encodes only digits corresponding to ZIP or ZIP+4 codes using half- and full-height bars, similar to 1D barcodes. Each digit is represented by five bars, two of which are full height.

The code example below shows how to generate a Postnet barcode.

How to get BarCodeInstance

// Generate a Postnet barcode
var gen = new BarCodeInstance.BarcodeGenerator("Postnet", "1159628792");
gen.Parameters.Barcode.XDimension = "3px";
document.getElementById("img").src = gen.GenerateBarCodeImage(); // Display barcode image

gen.delete();

RM4SCC

RM4SCC can encode only digits and uppercase English alphabet characters. It follows 1D barcode parameters, with each character represented by four bars: two extending upward and two downward. This bar arrangement creates 36 possible combinations, representing 10 digits and 26 letters.

The following code snippet demonstrates how to generate an RM4SCC barcode.

How to get BarCodeInstance

// Generate an RM4SCC barcode
var gen = new BarCodeInstance.BarcodeGenerator("RM4SCC", "123ABC");
gen.Parameters.Barcode.XDimension = "3px";
document.getElementById("img").src = gen.GenerateBarCodeImage(); // Display barcode image

gen.delete();

Javascript-Cpp: Complex Barcode Types

Mon, 01 Jan 0001 00:00:00 +0000

Javascript-Cpp: Barcode Recognition - Read Barcodes in JavaScript

Mon, 01 Jan 0001 00:00:00 +0000

Javascript-Cpp: How to Get BarCode Module Instance

Mon, 01 Jan 0001 00:00:00 +0000

Using the Global Module Instance with Aspose.BarCode.JS.Cpp.js

When working with the Aspose.BarCode.JS.Cpp.js library, it is essential to obtain a global module instance to access its features throughout your application. This guide explains how to load, initialize, and store the BarCode module as a global instance.

Prerequisites

Before initializing the BarCode module, ensure the Aspose.BarCode.JS.Cpp.js script is included in your HTML file. This step is required for the library to function properly.

<script type="text/javascript" src="Aspose.BarCode.JS.Cpp.js" async onload="initializeModule()"></script>
<script>
// Global BarCode module instance
var BarCodeInstance;

// Async function for module initialization
async function initializeModule() {
    try {
        // Load the BarCode module and store it in BarCodeInstance
        BarCodeInstance = await BarCode();
        console.log('BarCode module has loaded');
        
        // Additional code to enable barcode-related controls can be placed here
    } catch (error) {
        // Handle any errors that may occur during initialization
        console.error("BarCode module initialization error:", error);
    }
}
</script>

Javascript-Cpp: How to Run Aspose.BarCode Examples in JavaScript

Mon, 01 Jan 0001 00:00:00 +0000

Software Requirements

1. Web Browser

Modern Web Browsers: WebAssembly is supported in all major modern browsers. To run a WebAssembly application, you should ensure that you are using one of the following:
- Google Chrome (Version 57+)
- Mozilla Firefox (Version 52+)
- Safari (Version 11+ for macOS and iOS)
- Microsoft Edge (Version 16+)
- Opera (Version 44+)
Browser Settings: Ensure that WebAssembly is enabled in the browser. In most cases, it is enabled by default, but you can check the browser’s settings or developer tools for confirmation.

2. Operating System

Cross-Platform Compatibility: WebAssembly applications run in the browser, so they are generally independent of the underlying operating system. However, some performance and integration benefits can vary:
- Windows: Works well with the latest versions of Chrome, Edge, Firefox, and Opera.
- macOS: Runs WebAssembly applications with Safari, Chrome, Firefox, and Opera.
- Linux: Compatible with major browsers such as Chrome, Firefox, and Opera.
Mobile Devices: Most modern mobile browsers support WebAssembly, so WebAssembly apps can run on smartphones and tablets with Android or iOS.

3. Web Server (Optional but Recommended)

Serving WebAssembly Files: While you can open a .html file containing WebAssembly code directly in your browser, it’s generally better to serve it via a web server to handle features like CORS (Cross-Origin Resource Sharing) and improved security.
Simple Local Servers:
- Python HTTP Server: python3 -m http.server
- Node.js http-server: Install via npm install -g http-server and run with http-server.
Production Servers: Use a web server like Apache, Nginx, or nginx for deploying WebAssembly apps to a public web environment.

Download Examples from GitHub

All code examples available for Aspose.BarCode for JavaScript via C++ are hosted on GitHub. The project requires at least fully updated Visual Studio 2022 with .Net Framework 4.8 and .Net 6.0 or later versions installed.
To work with it, the following steps should be executed:

Either clone the repository using a preferred GitHub client or download the ZIP file from here
Extract the contents of the ZIP file to any folder on your computer. All examples are located in Examples folder
Check the file with the Visual Studio solution, Aspose.BarCode.Examples.CSharp.sln, in the folder
Open the solution file in Visual Studio and build a new project
Upon the first run, the dependencies will be downloaded automatically through NuGet
Check the Data folder in the root of Examples that contains the input files used in the provided code examples. You must download the Data folder together with the project
Open the RunExamples.cs file: all examples can be called from here
Uncomment the examples to be run within the project

In case of any issues with setting up or running code examples, reach out to Technical Support Forum.

How to Contribute

If you wish to add or improve a code example, we encourage you to contribute to the project. All examples and showcase projects provided in this repository are open source and can be freely used in your applications.

To contribute, you can fork the repository, edit the source code, and create a pull request. We will review the changes and include them in the repository if we find them helpful.