Generate QR code with PHP_PHP tutorial

Parameter description:

cht=qr: necessary parameter, fixed value , indicating that a QR code is to be generated

chs=x: Necessary parameters, generated QR code size, the unit is pixels, the currently generated QR codes are all square, so both width and height values ​​are set to the same value

chl=: Necessary parameter to generate the information contained in the QR code, which can be numbers, characters, binary information, and Chinese characters. Data types cannot be mixed, and the data must be UTF-8 URL-encoded. If the information that needs to be transferred exceeds 2K bytes, the POST method needs to be used

choe=: Optional parameter, encoding format. Including three options: UTF-8/Shift_JIS/ISO-8859-1, the default is UTF-8.

chld=|: optional parameter,

Error_correction_level: Error tolerance level (divided into four levels, L-default: can identify 7% of the data that has been lost; M-can identify 15% of the data that has been lost; Q-can identify 25% of the data that has been lost; H-Can identify data that has lost 30%)

Margin: the distance between the generated QR code and the image border

Example 1: Scan the QR code to open the URL (API)

Copy code

//QR code information, encoded with urlencode

$data = urlencode('http://www.baidu.com');

//Generate QR code size

$size = '300x300';

//Complete API address

$qrurl = "http://chart.googleapis.com/chart?chs=$size&cht=qr&chl=$data&chld=L|1&choe=UTF-8";

//Get the QR code

$qrcode = file_get_contents($qrurl);

//Output picture

header('Content-type: image/png');

echo $qrcode;

Copy code

After opening a website, we need to realize the purpose of returning to the original. Scan the QR code and import the company information into the address book, that is, include a business card information in the QR code. In fact, the QR code is to put a business card into the address book. It converts piles of information into the form of pictures, and it doesn't care what this pile of information looks like. What really cares about this information is the tool for scanning QR codes. Taking the above example, when you use WeChat to scan QR codes, After QR code, WeChat reads the data stored in the QR code, and then tries to identify it. When it finds that the content is a Baidu URL, it uses a browser to open it. Similarly, when it finds that the content is a bunch of simple text data When it is displayed in the form of text, WeChat can also identify whether the content of the QR code is an electronic business card in vcard format. Most of our mobile phone address books are imported and exported in this format, so we can directly The QR code contains a standard vcard electronic business card, which allows the scanning tool to recognize it as an address book.

Copy code

The vcard format reference is as follows:

BEGIN:VCARD

VERSION:3.0

FN: Username

TEL;CELL;VOICE:18858140621

TEL;WORK;VOICE:0358-2157466

TEL;WORK;FAX:0358-2157466

EMAIL;PREF;INTERNET:lzw#lzw.me

URL:http://lzw.me

orG:Zhiwen Studio

ROLE:Product Department

TITLE:CTO

ADR;WORK;POSTAL: No. 35, North Fourth Ring Middle Road, Chaoyang District, Beijing; 100101

REV:2012-12-27T08:30:02Z

END:VCARD

If you want to customize the required format in more detail, please Baidu vcard format standard.

Copy code

Example 2: Generate a business card QR code (API)

Copy code

//Construct a vcard format data

$vcard =

"BEGIN:VCARD".

"nVERSION:3.0".

"nFN: Xiaobian Luoluo".

"nTEL;CELL;VOICE:18858140621".

"nTEL;WORK;VOICE:0358－2157466".

"nEMAIL:luoluo@qq.com".

"nURL:http://www.baidu.com".

"nADR: Binjiang District, Hangzhou City, Zhejiang Province".

"nEND:VCARD";

//QR code information, encoded with urlencode

$data = urlencode($vcard);

//Generate QR code size

$size = '300x300';

//Complete API address

$qrurl = "http://chart.googleapis.com/chart?chs=$size&cht=qr&chl=$data&chld=L|1&choe=UTF-8";

//Get the QR code

$qrcode = file_get_contents($qrurl);

//Output picture

header('Content-type: image/png');

echo $qrcode;

Copy code

So far, our goal of returning to the original has been basically achieved, but in actual use, because the above assembled url was directly added to the src attribute of the img tag, there was a slight problem, because our business card information is relatively large , resulting in a QR code generation error, which has been marked in red font at the beginning of this article. The get method can only transfer up to 2K large data. When the data is larger than 2K, we need to use a POST request, so in actual use, you can first Get the QR code through POST and save it as a local image, and then directly call the local image.

Method 2: Use PHP QR CODE to generate QR code

Official homepage: http://phpqrcode.sourceforge.net

Download address: http://sourceforge.net/projects/phpqrcode/

Usage: QRcode::png($data, $filename, $errorCorrectionLevel, $matrixPointSize, $margin);

* $data data

* $filename generates a QR code saving path. If it is false, it will be output directly to the browser

　*$errorCorrectionLevel error handling level L, M, Q, H; the same as the error correction level in Google API

　 * $matrixPointSize Pixels for each black point

* $margin The white border pixels around the image

Example 3: Scan the QR code to open the URL (phpqrcode)

Copy code

// Contains qrlib.php or phpqrcode.php

//Including qrlib.php needs to be put together with other files; phpqrcode.php is the merged version and only needs to include this file, but the generated image is slow and inaccurate

include('./phpqrcode/qrlib.php');

// QR code data

$data = 'http://www.111cn.net';

// Correction level: L, M, Q, H

$errorCorrectionLevel = 'L';

//Point size: 1 to 10

$matrixPointSize = 5;

QRcode::png($data, false, $errorCorrectionLevel, $matrixPointSize, 2);

Copy code

Example 2: Generate a business card QR code (phpqrcode)

Copy code

// Contains qrlib.php or phpqrcode.php

include('./phpqrcode/qrlib.php');

//Construct vcard data

$vcard =

"BEGIN:VCARD".

"nVERSION:3.0".

"nFN:王歌".

"nTEL;CELL;VOICE:18858140621".

"nTEL;WORK;VOICE:0358－2157466".

"nEMAIL:wang@qq.com".

"nURL:http://www.mailuow.com".

"nADR: No. 1750, Jianghong Road, Binjiang District, Hangzhou City, Zhejiang Province".

"nEND:VCARD";

// Correction level: L, M, Q, H

$errorCorrectionLevel = 'L';

//Point size: 1 to 10

$matrixPointSize = 4;

QRcode::png($vcard, false, $errorCorrectionLevel, $matrixPointSize, 2);

http://www.bkjia.com/PHPjc/771403.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/771403.htmlTechArticleParameter description: cht=qr: necessary parameter, fixed value qr, indicating that a QR code is to be generated chs=widthxheight: Necessary parameters, the size of the generated QR code, the unit is pixels, the currently generated QR codes are...

Statement of this Website

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress images for free

Clothoff.io

AI clothes remover

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Show More

Hot Article

Assassin's Creed Shadows: Seashell Riddle Solution

4 weeks ago By DDD

What's New in Windows 11 KB5054979 & How to Fix Update Issues

3 weeks ago By DDD

Where to find the Crane Control Keycard in Atomfall

4 weeks ago By DDD

Roblox: Dead Rails - How To Complete Every Challenge

1 months ago By DDD

How to fix KB5055523 fails to install in Windows 11?

2 weeks ago By DDD

Show More

Hot Tools

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Show More

Hot Topics

Where is the login entrance for gmail email?

7733

15

Java Tutorial

1643

14

CakePHP Tutorial

1397

52

Laravel Tutorial

1290

25

PHP Tutorial

1233

29

Show More

Related knowledge

iOS 18 adds a new 'Recovered' album function to retrieve lost or damaged photos Jul 18, 2024 am 05:48 AM

Apple's latest releases of iOS18, iPadOS18 and macOS Sequoia systems have added an important feature to the Photos application, designed to help users easily recover photos and videos lost or damaged due to various reasons. The new feature introduces an album called "Recovered" in the Tools section of the Photos app that will automatically appear when a user has pictures or videos on their device that are not part of their photo library. The emergence of the "Recovered" album provides a solution for photos and videos lost due to database corruption, the camera application not saving to the photo library correctly, or a third-party application managing the photo library. Users only need a few simple steps

Detailed tutorial on establishing a database connection using MySQLi in PHP Jun 04, 2024 pm 01:42 PM

How to use MySQLi to establish a database connection in PHP: Include MySQLi extension (require_once) Create connection function (functionconnect_to_db) Call connection function ($conn=connect_to_db()) Execute query ($result=$conn->query()) Close connection ( $conn->close())

How to handle database connection errors in PHP Jun 05, 2024 pm 02:16 PM

To handle database connection errors in PHP, you can use the following steps: Use mysqli_connect_errno() to obtain the error code. Use mysqli_connect_error() to get the error message. By capturing and logging these error messages, database connection issues can be easily identified and resolved, ensuring the smooth running of your application.

What are the advantages and disadvantages of C++ compared to other web development languages? Jun 03, 2024 pm 12:11 PM

The advantages of C++ in web development include speed, performance, and low-level access, while limitations include a steep learning curve and memory management requirements. When choosing a web development language, developers should consider the advantages and limitations of C++ based on application needs.

How to use database callback functions in Golang? Jun 03, 2024 pm 02:20 PM

Using the database callback function in Golang can achieve: executing custom code after the specified database operation is completed. Add custom behavior through separate functions without writing additional code. Callback functions are available for insert, update, delete, and query operations. You must use the sql.Exec, sql.QueryRow, or sql.Query function to use the callback function.

How to save JSON data to database in Golang? Jun 06, 2024 am 11:24 AM

JSON data can be saved into a MySQL database by using the gjson library or the json.Unmarshal function. The gjson library provides convenience methods to parse JSON fields, and the json.Unmarshal function requires a target type pointer to unmarshal JSON data. Both methods require preparing SQL statements and performing insert operations to persist the data into the database.

The potential of C++ in mobile app development: Talent and resources Jun 03, 2024 pm 03:11 PM

C++ has great potential in mobile development because of: a huge developer community and rich learning resources; efficient memory management and low-level control, bringing excellent performance; WORA model, which can be written once and run across Android, iOS, and Windows; widely Used for game engine development, low latency and resource management functions meet high-performance game requirements.

MySQL: Simple Concepts for Easy Learning Apr 10, 2025 am 09:29 AM

MySQL is an open source relational database management system. 1) Create database and tables: Use the CREATEDATABASE and CREATETABLE commands. 2) Basic operations: INSERT, UPDATE, DELETE and SELECT. 3) Advanced operations: JOIN, subquery and transaction processing. 4) Debugging skills: Check syntax, data type and permissions. 5) Optimization suggestions: Use indexes, avoid SELECT* and use transactions.

See all articles