Secrets of generating barcodes with PHP_php skills

1. What is a barcode?

Baidu Encyclopedia definition: A barcode is a graphic identifier that expresses a set of information by arranging multiple black bars and blanks of varying widths according to certain encoding rules. A common barcode is a pattern consisting of black bars (referred to as bars) and white bars (referred to as spaces) with very different reflectivities arranged in parallel lines. In daily life, barcodes can indicate the country of production, manufacturer, product name, production date, book classification number, mailing address starting and ending, category, date and many other information. For details on the barcode encoding format, please refer to

For printed coupons, merchants need to use a validator to read the barcode to obtain its validity.

2. How to generate barcode?

First find powerful open source information, download the barcodegen.1d-php5.v5.0.1.zip version from the barcode official website, and then unzip the file and put it in the root directory of your Apache server

2.1 File structure:

2.2 Detailed analysis

(1) The class folder is a class that has been packaged to generate barcodes and only needs to be called.

(2) index.php is a function to generate barcodes with optional conditions, and is the entrance to the main program, while the html folder is the referenced code provided, and code39.php refers to the default encoding format.

<&#63;php 
header('Location: html/code39.php'); 
&#63;> 

(3) test.php is another example, directly generating HELLO barcode through code.

View Code  
 
<&#63;php 
// 引用class文件夹对应的类 
require_once('class/BCGFontFile.php'); 
require_once('class/BCGColor.php'); 
require_once('class/BCGDrawing.php'); 
 
// 条形码的编码格式 
require_once('class/BCGcode39.barcode.php'); 
 
// 加载字体大小 
$font = new BCGFontFile('./class/font/Arial.ttf', 18); 
 
//颜色条形码 
$color_black = new BCGColor(0, 0, 0); 
$color_white = new BCGColor(255, 255, 255); 
 
$drawException = null; 
try { 
  $code = new BCGcode39(); 
  $code->setScale(2);  
  $code->setThickness(30); // 条形码的厚度 
  $code->setForegroundColor($color_black); // 条形码颜色 
  $code->setBackgroundColor($color_white); // 空白间隙颜色 
  $code->setFont($font); //  
  $code->parse('HELLO'); // 条形码需要的数据内容 
} catch(Exception $exception) { 
  $drawException = $exception; 
} 
 
//根据以上条件绘制条形码 
$drawing = new BCGDrawing('', $color_white); 
if($drawException) { 
  $drawing->drawException($drawException); 
} else { 
  $drawing->setBarcode($code); 
  $drawing->draw(); 
} 
 
// 生成PNG格式的图片 
header('Content-Type: image/png'); 
 
 
$drawing->finish(BCGDrawing::IMG_FORMAT_PNG); 
&#63;>

3. Practical application

After having a general understanding of the above, we can re-integrate the code to make it more convenient to use.

First create a new buildcode.php file, rewrite it based on the test.php file, and obtain data from the requested file:

1). Barcode encoding format

2). Data content required by barcode

View Code  
<&#63;php 
// Including all required classes 
require_once('class/BCGFontFile.php'); 
require_once('class/BCGColor.php'); 
require_once('class/BCGDrawing.php');  
$codebar = $_REQUEST['codebar']; //条形码将要数据的内容  
// Including the barcode technology 
require_once('class/'.$codebar.'.barcode.php');  
// Loading Font 
$font = new BCGFontFile('./class/font/Arial.ttf', 12);  
// The arguments are R, G, B for color. 
$color_black = new BCGColor(0, 0, 0); 
$color_white = new BCGColor(255, 255, 255);  
$drawException = null; 
try { 
  $code = new $codebar();//实例化对应的编码格式 
  $code->setScale(2); // Resolution 
  $code->setThickness(23); // Thickness 
  $code->setForegroundColor($color_black); // Color of bars 
  $code->setBackgroundColor($color_white); // Color of spaces 
  $code->setFont($font); // Font (or 0) 
  $text = $_REQUEST['text']; //条形码将要数据的内容 
  $code->parse($text); 
} catch(Exception $exception) { 
  $drawException = $exception; 
}  
/* Here is the list of the arguments 
 - Filename (empty : display on screen) 
 - Background color */ 
$drawing = new BCGDrawing('', $color_white); 
if($drawException) { 
  $drawing->drawException($drawException); 
} else { 
  $drawing->setBarcode($code); 
  $drawing->draw(); 
}  
// Header that says it is an image (remove it if you save the barcode to a file) 
header('Content-Type: image/png');  
// Draw (or save) the image into PNG format. 
$drawing->finish(BCGDrawing::IMG_FORMAT_PNG); 
&#63;> 

Then create a new test.html file and request data from buildcode.php

<!DOCTYPE html> 
<html> 
<head> 
<title>Test with embedded image</title> 
</head> 
<body> 
 <img src="buildcode.php&#63;codebar=BCGcode39&text=abc123"/> 
</body> 
</html> 

Finally visit, the browser directly generates the barcode in png format

The encoding format supported by codebar can be requested by the user:

/*'BCGcodabar','BCGcode11','BCGcode39','BCGcode39extended','BCGcode93', 
'BCGcode128','BCGean8','BCGean13','BCGisbn','BCGi25','BCGs25','BCGmsi', 
'BCGupca','BCGupce','BCGupcext2','BCGupcext5','BCGpostnet','BCGothercode'*/　
All that’s left is verification

4. Verification

How do we verify whether the barcode is valid, that is, whether the content in the barcode can be read.

Save the image first, then access the verification function provided by the official website, upload the image and it’s OK!

Today I will reveal with you how PHP generates barcodes. I hope you can have a general understanding of the formation of barcodes and it will be helpful for future study.